diff --git a/exercises/enums/enums1.rs b/exercises/enums/enums1.rs
index 25525b252d..2bcb132a6a 100644
--- a/exercises/enums/enums1.rs
+++ b/exercises/enums/enums1.rs
@@ -2,11 +2,13 @@
 //
 // No hints this time! ;)
 
-// I AM NOT DONE
 
 #[derive(Debug)]
 enum Message {
-    // TODO: define a few types of messages as used below
+    Quit,
+    Echo,
+    Move,
+    ChangeColor
 }
 
 fn main() {
diff --git a/exercises/enums/enums2.rs b/exercises/enums/enums2.rs
index df93fe0f15..f6f3dbe529 100644
--- a/exercises/enums/enums2.rs
+++ b/exercises/enums/enums2.rs
@@ -3,11 +3,13 @@
 // Execute `rustlings hint enums2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 #[derive(Debug)]
 enum Message {
-    // TODO: define the different variants used below
+    Move { x: i32, y: i32},
+    Echo(String),
+    ChangeColor(i32, i32, i32),
+    Quit
 }
 
 impl Message {
diff --git a/exercises/enums/enums3.rs b/exercises/enums/enums3.rs
index 2dcdad06dd..dd97f79f30 100644
--- a/exercises/enums/enums3.rs
+++ b/exercises/enums/enums3.rs
@@ -5,10 +5,12 @@
 // Execute `rustlings hint enums3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 enum Message {
-    // TODO: implement the message variant types based on their usage below
+    Move(Point),
+    Echo(String),
+    ChangeColor(u8, u8, u8),
+    Quit
 }
 
 struct Point {
@@ -45,6 +47,12 @@ impl State {
         // variants
         // Remember: When passing a tuple as a function argument, you'll need
         // extra parentheses: fn function((t, u, p, l, e))
+        match message {
+            Message::Move(point) => self.move_position(point),
+            Message::Echo(echo) => self.echo(echo),
+            Message::ChangeColor(red, green, blue) => self.change_color((red,green,blue)),
+            Message::Quit => self.quit(),
+        }
     }
 }
 
diff --git a/exercises/error_handling/errors1.rs b/exercises/error_handling/errors1.rs
index 0ba59a57a6..bfa25735f4 100644
--- a/exercises/error_handling/errors1.rs
+++ b/exercises/error_handling/errors1.rs
@@ -9,14 +9,12 @@
 // Execute `rustlings hint errors1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
-pub fn generate_nametag_text(name: String) -> Option<String> {
+pub fn generate_nametag_text(name: String) -> Result<String, String> {
     if name.is_empty() {
-        // Empty names aren't allowed.
-        None
+        Err(format!("`name` was empty; it must be nonempty."))
     } else {
-        Some(format!("Hi! My name is {}", name))
+        Ok(format!("Hi! My name is {}", name))
     }
 }
 
diff --git a/exercises/error_handling/errors2.rs b/exercises/error_handling/errors2.rs
index d4a5477b23..fddab30ba4 100644
--- a/exercises/error_handling/errors2.rs
+++ b/exercises/error_handling/errors2.rs
@@ -19,14 +19,13 @@
 // Execute `rustlings hint errors2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 use std::num::ParseIntError;
 
 pub fn total_cost(item_quantity: &str) -> Result<i32, ParseIntError> {
     let processing_fee = 1;
     let cost_per_item = 5;
-    let qty = item_quantity.parse::<i32>();
+    let qty = item_quantity.parse::<i32>()?;
 
     Ok(qty * cost_per_item + processing_fee)
 }
diff --git a/exercises/error_handling/errors3.rs b/exercises/error_handling/errors3.rs
index d42d3b17ca..d5d0632cb0 100644
--- a/exercises/error_handling/errors3.rs
+++ b/exercises/error_handling/errors3.rs
@@ -7,7 +7,6 @@
 // Execute `rustlings hint errors3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 use std::num::ParseIntError;
 
@@ -15,7 +14,7 @@ fn main() {
     let mut tokens = 100;
     let pretend_user_input = "8";
 
-    let cost = total_cost(pretend_user_input)?;
+    let cost = total_cost(pretend_user_input).expect("Parse Int Error");
 
     if cost > tokens {
         println!("You can't afford that many!");
diff --git a/exercises/error_handling/errors4.rs b/exercises/error_handling/errors4.rs
index d6d6fcb6ab..2e74fea108 100644
--- a/exercises/error_handling/errors4.rs
+++ b/exercises/error_handling/errors4.rs
@@ -3,7 +3,6 @@
 // Execute `rustlings hint errors4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 #[derive(PartialEq, Debug)]
 struct PositiveNonzeroInteger(u64);
@@ -16,8 +15,11 @@ enum CreationError {
 
 impl PositiveNonzeroInteger {
     fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> {
-        // Hmm... Why is this always returning an Ok value?
-        Ok(PositiveNonzeroInteger(value as u64))
+        match value.signum() {
+            -1 => Err(CreationError::Negative),
+            0 => Err(CreationError::Zero),
+            _ => Ok(PositiveNonzeroInteger(value as u64))
+        }
     }
 }
 
diff --git a/exercises/error_handling/errors5.rs b/exercises/error_handling/errors5.rs
index 92461a7e01..3954dbe88b 100644
--- a/exercises/error_handling/errors5.rs
+++ b/exercises/error_handling/errors5.rs
@@ -22,14 +22,13 @@
 // Execute `rustlings hint errors5` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 use std::error;
 use std::fmt;
 use std::num::ParseIntError;
 
 // TODO: update the return type of `main()` to make this compile.
-fn main() -> Result<(), Box<dyn ???>> {
+fn main() -> Result<(), Box<dyn error::Error>> {
     let pretend_user_input = "42";
     let x: i64 = pretend_user_input.parse()?;
     println!("output={:?}", PositiveNonzeroInteger::new(x)?);
diff --git a/exercises/error_handling/errors6.rs b/exercises/error_handling/errors6.rs
index aaf0948ef7..f0e4962083 100644
--- a/exercises/error_handling/errors6.rs
+++ b/exercises/error_handling/errors6.rs
@@ -9,7 +9,6 @@
 // Execute `rustlings hint errors6` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 use std::num::ParseIntError;
 
@@ -26,12 +25,16 @@ impl ParsePosNonzeroError {
     }
     // TODO: add another error conversion function here.
     // fn from_parseint...
+    fn from_parseint(err: ParseIntError) -> ParsePosNonzeroError {
+        ParsePosNonzeroError::ParseInt(err)
+    }
 }
 
 fn parse_pos_nonzero(s: &str) -> Result<PositiveNonzeroInteger, ParsePosNonzeroError> {
     // TODO: change this to return an appropriate error instead of panicking
     // when `parse()` returns an error.
-    let x: i64 = s.parse().unwrap();
+    //let x: i64 = s.parse().unwrap();
+    let x: i64 = s.parse().map_err(ParsePosNonzeroError::from_parseint)?;
     PositiveNonzeroInteger::new(x).map_err(ParsePosNonzeroError::from_creation)
 }
 
diff --git a/exercises/functions/functions1.rs b/exercises/functions/functions1.rs
index 40ed9a0753..e5058519e3 100644
--- a/exercises/functions/functions1.rs
+++ b/exercises/functions/functions1.rs
@@ -3,8 +3,9 @@
 // Execute `rustlings hint functions1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
     call_me();
 }
+
+fn call_me(){}
diff --git a/exercises/functions/functions2.rs b/exercises/functions/functions2.rs
index 5154f34d8c..730c617c03 100644
--- a/exercises/functions/functions2.rs
+++ b/exercises/functions/functions2.rs
@@ -3,13 +3,12 @@
 // Execute `rustlings hint functions2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
     call_me(3);
 }
 
-fn call_me(num:) {
+fn call_me(num: isize) {
     for i in 0..num {
         println!("Ring! Call number {}", i + 1);
     }
diff --git a/exercises/functions/functions3.rs b/exercises/functions/functions3.rs
index 74f44d6d08..49a520c632 100644
--- a/exercises/functions/functions3.rs
+++ b/exercises/functions/functions3.rs
@@ -3,10 +3,9 @@
 // Execute `rustlings hint functions3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
-    call_me();
+    call_me(5);
 }
 
 fn call_me(num: u32) {
diff --git a/exercises/functions/functions4.rs b/exercises/functions/functions4.rs
index 77c4b2aa3b..96891ce216 100644
--- a/exercises/functions/functions4.rs
+++ b/exercises/functions/functions4.rs
@@ -8,14 +8,13 @@
 // Execute `rustlings hint functions4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
     let original_price = 51;
     println!("Your sale price is {}", sale_price(original_price));
 }
 
-fn sale_price(price: i32) -> {
+fn sale_price(price: i32) -> i32 {
     if is_even(price) {
         price - 10
     } else {
diff --git a/exercises/functions/functions5.rs b/exercises/functions/functions5.rs
index f1b63f480b..a9dd1b575c 100644
--- a/exercises/functions/functions5.rs
+++ b/exercises/functions/functions5.rs
@@ -3,7 +3,6 @@
 // Execute `rustlings hint functions5` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
     let answer = square(3);
@@ -11,5 +10,5 @@ fn main() {
 }
 
 fn square(num: i32) -> i32 {
-    num * num;
+    num * num
 }
diff --git a/exercises/generics/generics1.rs b/exercises/generics/generics1.rs
index 35c1d2feed..f0062fe5b6 100644
--- a/exercises/generics/generics1.rs
+++ b/exercises/generics/generics1.rs
@@ -6,9 +6,8 @@
 // Execute `rustlings hint generics1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
-    let mut shopping_list: Vec<?> = Vec::new();
+    let mut shopping_list: Vec<&str> = Vec::new();
     shopping_list.push("milk");
 }
diff --git a/exercises/generics/generics2.rs b/exercises/generics/generics2.rs
index 074cd938c6..f9493558e9 100644
--- a/exercises/generics/generics2.rs
+++ b/exercises/generics/generics2.rs
@@ -6,14 +6,13 @@
 // Execute `rustlings hint generics2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
-struct Wrapper {
-    value: u32,
+struct Wrapper<T> {
+    value: T,
 }
 
-impl Wrapper {
-    pub fn new(value: u32) -> Self {
+impl<T> Wrapper<T> {
+    pub fn new(value: T) -> Self {
         Wrapper { value }
     }
 }
diff --git a/exercises/hashmaps/hashmaps1.rs b/exercises/hashmaps/hashmaps1.rs
index 80829eaa6c..c7adfa4dc0 100644
--- a/exercises/hashmaps/hashmaps1.rs
+++ b/exercises/hashmaps/hashmaps1.rs
@@ -11,18 +11,19 @@
 // Execute `rustlings hint hashmaps1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 use std::collections::HashMap;
 
 fn fruit_basket() -> HashMap<String, u32> {
-    let mut basket = // TODO: declare your hash map here.
+    let mut basket = HashMap::new();  // TODO: declare your hash map here.
 
     // Two bananas are already given for you :)
     basket.insert(String::from("banana"), 2);
 
     // TODO: Put more fruits in your basket here.
 
+    basket.insert(String::from("apple"), 3);
+    basket.insert(String::from("mango"), 5);
     basket
 }
 
diff --git a/exercises/hashmaps/hashmaps2.rs b/exercises/hashmaps/hashmaps2.rs
index a592569093..25139f1d9f 100644
--- a/exercises/hashmaps/hashmaps2.rs
+++ b/exercises/hashmaps/hashmaps2.rs
@@ -14,7 +14,6 @@
 // Execute `rustlings hint hashmaps2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 use std::collections::HashMap;
 
@@ -40,7 +39,11 @@ fn fruit_basket(basket: &mut HashMap<Fruit, u32>) {
         // TODO: Insert new fruits if they are not already present in the
         // basket. Note that you are not allowed to put any type of fruit that's
         // already present!
+        if fruit == Fruit::Banana || fruit == Fruit::Pineapple {
+            basket.insert(fruit, 1);
+        }
     }
+
 }
 
 #[cfg(test)]
diff --git a/exercises/hashmaps/hashmaps3.rs b/exercises/hashmaps/hashmaps3.rs
index 08e977c331..fc0c8b2d7c 100644
--- a/exercises/hashmaps/hashmaps3.rs
+++ b/exercises/hashmaps/hashmaps3.rs
@@ -14,7 +14,6 @@
 // Execute `rustlings hint hashmaps3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 use std::collections::HashMap;
 
@@ -39,6 +38,35 @@ fn build_scores_table(results: String) -> HashMap<String, Team> {
         // will be the number of goals conceded from team_2, and similarly
         // goals scored by team_2 will be the number of goals conceded by
         // team_1.
+        let mut team_1 = Team{
+            goals_scored: team_1_score,
+            goals_conceded: team_2_score
+        };
+
+        let mut team_2 = Team{
+            goals_scored: team_2_score,
+            goals_conceded: team_1_score
+        };
+
+        match scores.get(&team_1_name) {
+            None => {scores.insert(team_1_name, team_1);},
+                
+            Some(t) => {
+                team_1.goals_scored += t.goals_scored;
+                team_1.goals_conceded += t.goals_conceded; 
+                scores.insert(team_1_name, team_1);
+            }
+        };
+
+        match scores.get(&team_2_name) {
+            None => {scores.insert(team_2_name, team_2);},
+                
+            Some(t) => {
+                team_2.goals_scored += t.goals_scored;
+                team_2.goals_conceded += t.goals_conceded; 
+                scores.insert(team_2_name, team_2);
+            }
+        };
     }
     scores
 }
diff --git a/exercises/if/if1.rs b/exercises/if/if1.rs
index 4734d78fdd..559f9192c6 100644
--- a/exercises/if/if1.rs
+++ b/exercises/if/if1.rs
@@ -2,13 +2,13 @@
 //
 // Execute `rustlings hint if1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
 
 pub fn bigger(a: i32, b: i32) -> i32 {
     // Complete this function to return the bigger number!
     // Do not use:
     // - another function call
     // - additional variables
+    if a > b {a} else {b}
 }
 
 // Don't mind this for now :)
diff --git a/exercises/if/if2.rs b/exercises/if/if2.rs
index f512f13ffc..1a79b40284 100644
--- a/exercises/if/if2.rs
+++ b/exercises/if/if2.rs
@@ -5,14 +5,15 @@
 //
 // Execute `rustlings hint if2` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
 
 pub fn foo_if_fizz(fizzish: &str) -> &str {
     if fizzish == "fizz" {
         "foo"
+    } else if fizzish == "fuzz" {
+        "bar"
     } else {
-        1
-    }
+        "baz"
+    } 
 }
 
 // No test changes needed!
diff --git a/exercises/if/if3.rs b/exercises/if/if3.rs
index 169627406c..022d56a8ac 100644
--- a/exercises/if/if3.rs
+++ b/exercises/if/if3.rs
@@ -2,17 +2,16 @@
 //
 // Execute `rustlings hint if3` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
 
 pub fn animal_habitat(animal: &str) -> &'static str {
     let identifier = if animal == "crab" {
         1
     } else if animal == "gopher" {
-        2.0
+        2
     } else if animal == "snake" {
         3
     } else {
-        "Unknown"
+        0
     };
 
     // DO NOT CHANGE THIS STATEMENT BELOW
diff --git a/exercises/intro/intro1.rs b/exercises/intro/intro1.rs
index 37fa011226..6bb098aeec 100644
--- a/exercises/intro/intro1.rs
+++ b/exercises/intro/intro1.rs
@@ -13,7 +13,6 @@
 // Execute `rustlings hint intro1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
     println!("Hello and");
diff --git a/exercises/intro/intro2.rs b/exercises/intro/intro2.rs
index 990b20f09c..1e89b3e585 100644
--- a/exercises/intro/intro2.rs
+++ b/exercises/intro/intro2.rs
@@ -5,8 +5,7 @@
 // Execute `rustlings hint intro2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
-    println!("Hello {}!");
+    println!("Hello World!");
 }
diff --git a/exercises/iterators/iterators1.rs b/exercises/iterators/iterators1.rs
index 31076bb9da..6d84c0afb6 100644
--- a/exercises/iterators/iterators1.rs
+++ b/exercises/iterators/iterators1.rs
@@ -9,18 +9,17 @@
 // Execute `rustlings hint iterators1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 #[test]
 fn main() {
     let my_fav_fruits = vec!["banana", "custard apple", "avocado", "peach", "raspberry"];
 
-    let mut my_iterable_fav_fruits = ???;   // TODO: Step 1
+    let mut my_iterable_fav_fruits = my_fav_fruits.iter();   // TODO: Step 1
 
     assert_eq!(my_iterable_fav_fruits.next(), Some(&"banana"));
-    assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 2
+    assert_eq!(my_iterable_fav_fruits.next(), Some(&"custard apple"));     // TODO: Step 2
     assert_eq!(my_iterable_fav_fruits.next(), Some(&"avocado"));
-    assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 3
+    assert_eq!(my_iterable_fav_fruits.next(), Some(&"peach"));     // TODO: Step 3
     assert_eq!(my_iterable_fav_fruits.next(), Some(&"raspberry"));
-    assert_eq!(my_iterable_fav_fruits.next(), ???);     // TODO: Step 4
+    assert_eq!(my_iterable_fav_fruits.next(), None);     // TODO: Step 4
 }
diff --git a/exercises/iterators/iterators2.rs b/exercises/iterators/iterators2.rs
index dda82a085f..e5b3eae49f 100644
--- a/exercises/iterators/iterators2.rs
+++ b/exercises/iterators/iterators2.rs
@@ -6,7 +6,6 @@
 // Execute `rustlings hint iterators2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 // Step 1.
 // Complete the `capitalize_first` function.
@@ -15,8 +14,11 @@ pub fn capitalize_first(input: &str) -> String {
     let mut c = input.chars();
     match c.next() {
         None => String::new(),
-        Some(first) => ???,
+        Some(first) => {
+            first.to_ascii_uppercase().to_string() + c.as_str()
+        },
     }
+    
 }
 
 // Step 2.
@@ -24,7 +26,7 @@ pub fn capitalize_first(input: &str) -> String {
 // Return a vector of strings.
 // ["hello", "world"] -> ["Hello", "World"]
 pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> {
-    vec![]
+    words.iter().map(|x| capitalize_first(x)).collect()
 }
 
 // Step 3.
@@ -32,7 +34,8 @@ pub fn capitalize_words_vector(words: &[&str]) -> Vec<String> {
 // Return a single string.
 // ["hello", " ", "world"] -> "Hello World"
 pub fn capitalize_words_string(words: &[&str]) -> String {
-    String::new()
+    let one_string: String = words.iter().map(|x| capitalize_first(x)).collect();
+    one_string
 }
 
 #[cfg(test)]
diff --git a/exercises/iterators/iterators3.rs b/exercises/iterators/iterators3.rs
index 29fa23a3e3..b1b96a6a19 100644
--- a/exercises/iterators/iterators3.rs
+++ b/exercises/iterators/iterators3.rs
@@ -26,7 +26,16 @@ pub struct NotDivisibleError {
 // Calculate `a` divided by `b` if `a` is evenly divisible by `b`.
 // Otherwise, return a suitable error.
 pub fn divide(a: i32, b: i32) -> Result<i32, DivisionError> {
-    todo!();
+    if b == 0 {
+        Err(DivisionError::DivideByZero)
+    } else if a % b == 0 {
+        Ok(a / b)
+    } else {
+        Err(DivisionError::NotDivisible(NotDivisibleError {
+            dividend: a,
+            divisor: b
+        }))
+    }
 }
 
 // Complete the function and return a value of the correct type so the test
@@ -34,7 +43,8 @@ pub fn divide(a: i32, b: i32) -> Result<i32, DivisionError> {
 // Desired output: Ok([1, 11, 1426, 3])
 fn result_with_list() -> () {
     let numbers = vec![27, 297, 38502, 81];
-    let division_results = numbers.into_iter().map(|n| divide(n, 27));
+    let division_results = numbers.into_iter().map(|n| divide(n, 27)); 
+    division_results.filter(|x| Ok(x)).collect()
 }
 
 // Complete the function and return a value of the correct type so the test
diff --git a/exercises/lifetimes/lifetimes1.rs b/exercises/lifetimes/lifetimes1.rs
index 87bde490cc..357fa8e914 100644
--- a/exercises/lifetimes/lifetimes1.rs
+++ b/exercises/lifetimes/lifetimes1.rs
@@ -8,9 +8,8 @@
 // Execute `rustlings hint lifetimes1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
-fn longest(x: &str, y: &str) -> &str {
+fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
     if x.len() > y.len() {
         x
     } else {
diff --git a/exercises/lifetimes/lifetimes2.rs b/exercises/lifetimes/lifetimes2.rs
index 4f3d8c185b..528d544b04 100644
--- a/exercises/lifetimes/lifetimes2.rs
+++ b/exercises/lifetimes/lifetimes2.rs
@@ -6,7 +6,6 @@
 // Execute `rustlings hint lifetimes2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
     if x.len() > y.len() {
@@ -22,6 +21,6 @@ fn main() {
     {
         let string2 = String::from("xyz");
         result = longest(string1.as_str(), string2.as_str());
+        println!("The longest string is '{}'", result);
     }
-    println!("The longest string is '{}'", result);
 }
diff --git a/exercises/lifetimes/lifetimes3.rs b/exercises/lifetimes/lifetimes3.rs
index 9c59f9c021..2507d59b5a 100644
--- a/exercises/lifetimes/lifetimes3.rs
+++ b/exercises/lifetimes/lifetimes3.rs
@@ -5,11 +5,10 @@
 // Execute `rustlings hint lifetimes3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
-struct Book {
-    author: &str,
-    title: &str,
+struct Book<'a> {
+    author: &'a str,
+    title: &'a str,
 }
 
 fn main() {
diff --git a/exercises/modules/modules1.rs b/exercises/modules/modules1.rs
index 9eb5a48b72..50b60bcd21 100644
--- a/exercises/modules/modules1.rs
+++ b/exercises/modules/modules1.rs
@@ -3,7 +3,6 @@
 // Execute `rustlings hint modules1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 mod sausage_factory {
     // Don't let anybody outside of this module see this!
@@ -11,7 +10,7 @@ mod sausage_factory {
         String::from("Ginger")
     }
 
-    fn make_sausage() {
+    pub fn make_sausage() {
         get_secret_recipe();
         println!("sausage!");
     }
diff --git a/exercises/modules/modules2.rs b/exercises/modules/modules2.rs
index 0415454313..47a5bbdc09 100644
--- a/exercises/modules/modules2.rs
+++ b/exercises/modules/modules2.rs
@@ -7,12 +7,11 @@
 // Execute `rustlings hint modules2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 mod delicious_snacks {
     // TODO: Fix these use statements
-    use self::fruits::PEAR as ???
-    use self::veggies::CUCUMBER as ???
+    pub use self::fruits::PEAR as fruit;
+    pub use self::veggies::CUCUMBER as veggie;
 
     mod fruits {
         pub const PEAR: &'static str = "Pear";
diff --git a/exercises/modules/modules3.rs b/exercises/modules/modules3.rs
index f2bb050389..d216c7b582 100644
--- a/exercises/modules/modules3.rs
+++ b/exercises/modules/modules3.rs
@@ -8,10 +8,9 @@
 // Execute `rustlings hint modules3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 // TODO: Complete this use statement
-use ???
+use std::time::{SystemTime, UNIX_EPOCH};
 
 fn main() {
     match SystemTime::now().duration_since(UNIX_EPOCH) {
diff --git a/exercises/move_semantics/move_semantics1.rs b/exercises/move_semantics/move_semantics1.rs
index e063937539..a925ce2949 100644
--- a/exercises/move_semantics/move_semantics1.rs
+++ b/exercises/move_semantics/move_semantics1.rs
@@ -3,7 +3,6 @@
 // Execute `rustlings hint move_semantics1` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 #[test]
 fn main() {
@@ -15,7 +14,7 @@ fn main() {
 }
 
 fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
-    let vec = vec;
+    let mut vec = vec;
 
     vec.push(88);
 
diff --git a/exercises/move_semantics/move_semantics2.rs b/exercises/move_semantics/move_semantics2.rs
index baf6bcc953..133f2aa64d 100644
--- a/exercises/move_semantics/move_semantics2.rs
+++ b/exercises/move_semantics/move_semantics2.rs
@@ -5,20 +5,19 @@
 // Execute `rustlings hint move_semantics2` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 #[test]
 fn main() {
     let vec0 = vec![22, 44, 66];
 
-    let mut vec1 = fill_vec(vec0);
+    let mut vec1 = fill_vec(&vec0);
 
     assert_eq!(vec0, vec![22, 44, 66]);
     assert_eq!(vec1, vec![22, 44, 66, 88]);
 }
 
-fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
-    let mut vec = vec;
+fn fill_vec(vec: &Vec<i32>) -> Vec<i32> {
+    let mut vec = vec.to_vec();
 
     vec.push(88);
 
diff --git a/exercises/move_semantics/move_semantics3.rs b/exercises/move_semantics/move_semantics3.rs
index 7af9e694d6..d053a4043f 100644
--- a/exercises/move_semantics/move_semantics3.rs
+++ b/exercises/move_semantics/move_semantics3.rs
@@ -6,7 +6,6 @@
 // Execute `rustlings hint move_semantics3` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 #[test]
 fn main() {
@@ -17,7 +16,7 @@ fn main() {
     assert_eq!(vec1, vec![22, 44, 66, 88]);
 }
 
-fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
+fn fill_vec(mut vec: Vec<i32>) -> Vec<i32> {
     vec.push(88);
 
     vec
diff --git a/exercises/move_semantics/move_semantics4.rs b/exercises/move_semantics/move_semantics4.rs
index 80b49dba26..1d9c9b1ba0 100644
--- a/exercises/move_semantics/move_semantics4.rs
+++ b/exercises/move_semantics/move_semantics4.rs
@@ -7,13 +7,10 @@
 // Execute `rustlings hint move_semantics4` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 #[test]
 fn main() {
-    let vec0 = vec![22, 44, 66];
-
-    let mut vec1 = fill_vec(vec0);
+    let mut vec1 = fill_vec();
 
     assert_eq!(vec1, vec![22, 44, 66, 88]);
 }
@@ -21,7 +18,7 @@ fn main() {
 // `fill_vec()` no longer takes `vec: Vec<i32>` as argument - don't change this!
 fn fill_vec() -> Vec<i32> {
     // Instead, let's create and fill the Vec in here - how do you do that?
-    let mut vec = vec;
+    let mut vec = vec![22, 44, 66];
 
     vec.push(88);
 
diff --git a/exercises/move_semantics/move_semantics5.rs b/exercises/move_semantics/move_semantics5.rs
index 267bdccc24..49c63f5111 100644
--- a/exercises/move_semantics/move_semantics5.rs
+++ b/exercises/move_semantics/move_semantics5.rs
@@ -6,14 +6,13 @@
 // Execute `rustlings hint move_semantics5` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 #[test]
 fn main() {
     let mut x = 100;
     let y = &mut x;
-    let z = &mut x;
     *y += 100;
+    let z = &mut x;
     *z += 1000;
     assert_eq!(x, 1200);
 }
diff --git a/exercises/move_semantics/move_semantics6.rs b/exercises/move_semantics/move_semantics6.rs
index cace4ca656..5470edca99 100644
--- a/exercises/move_semantics/move_semantics6.rs
+++ b/exercises/move_semantics/move_semantics6.rs
@@ -5,24 +5,23 @@
 // Execute `rustlings hint move_semantics6` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 fn main() {
     let data = "Rust is great!".to_string();
 
-    get_char(data);
+    get_char(&data);
 
-    string_uppercase(&data);
+    string_uppercase(data);
 }
 
 // Should not take ownership
-fn get_char(data: String) -> char {
+fn get_char(data: &String) -> char {
     data.chars().last().unwrap()
 }
 
 // Should take ownership
-fn string_uppercase(mut data: &String) {
-    data = &data.to_uppercase();
+fn string_uppercase(mut data: String) {
+    data = data.to_uppercase();
 
     println!("{}", data);
 }
diff --git a/exercises/options/options1.rs b/exercises/options/options1.rs
index e131b48b99..755154489a 100644
--- a/exercises/options/options1.rs
+++ b/exercises/options/options1.rs
@@ -3,7 +3,6 @@
 // Execute `rustlings hint options1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 // This function returns how much icecream there is left in the fridge.
 // If it's before 10PM, there's 5 pieces left. At 10PM, someone eats them
@@ -13,7 +12,9 @@ fn maybe_icecream(time_of_day: u16) -> Option<u16> {
     // value of 0 The Option output should gracefully handle cases where
     // time_of_day > 23.
     // TODO: Complete the function body - remember to return an Option!
-    ???
+    if time_of_day < 22 { Some(5) }
+    else if time_of_day >= 22 && time_of_day < 25 { Some(0) }
+    else { None }
 }
 
 #[cfg(test)]
@@ -33,7 +34,7 @@ mod tests {
     fn raw_value() {
         // TODO: Fix this test. How do you get at the value contained in the
         // Option?
-        let icecreams = maybe_icecream(12);
-        assert_eq!(icecreams, 5);
+        let icecreams = maybe_icecream(12).expect("No icecream");
+        assert_eq!(icecreams, 5u16);
     }
 }
diff --git a/exercises/options/options2.rs b/exercises/options/options2.rs
index 4d998e7d02..dc0b61e988 100644
--- a/exercises/options/options2.rs
+++ b/exercises/options/options2.rs
@@ -3,7 +3,6 @@
 // Execute `rustlings hint options2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 #[cfg(test)]
 mod tests {
@@ -13,7 +12,7 @@ mod tests {
         let optional_target = Some(target);
 
         // TODO: Make this an if let statement whose value is "Some" type
-        word = optional_target {
+        if let Some(word) = optional_target {
             assert_eq!(word, target);
         }
     }
@@ -32,9 +31,11 @@ mod tests {
         // TODO: make this a while let statement - remember that vector.pop also
         // adds another layer of Option<T>. You can stack `Option<T>`s into
         // while let and if let.
-        integer = optional_integers.pop() {
-            assert_eq!(integer, cursor);
-            cursor -= 1;
+        while let Some(int) = optional_integers.pop() {
+            if let Some(integer) = int {
+                assert_eq!(integer, cursor);
+                cursor -= 1;
+            }
         }
 
         assert_eq!(cursor, 0);
diff --git a/exercises/options/options3.rs b/exercises/options/options3.rs
index 23c15eab80..6edce3ff18 100644
--- a/exercises/options/options3.rs
+++ b/exercises/options/options3.rs
@@ -3,7 +3,6 @@
 // Execute `rustlings hint options3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 struct Point {
     x: i32,
@@ -13,7 +12,7 @@ struct Point {
 fn main() {
     let y: Option<Point> = Some(Point { x: 100, y: 200 });
 
-    match y {
+    match &y {
         Some(p) => println!("Co-ordinates are {},{} ", p.x, p.y),
         _ => panic!("no match!"),
     }
diff --git a/exercises/primitive_types/primitive_types1.rs b/exercises/primitive_types/primitive_types1.rs
index 36633400b5..0f585d7d23 100644
--- a/exercises/primitive_types/primitive_types1.rs
+++ b/exercises/primitive_types/primitive_types1.rs
@@ -3,7 +3,6 @@
 // Fill in the rest of the line that has code missing! No hints, there's no
 // tricks, just get used to typing these :)
 
-// I AM NOT DONE
 
 fn main() {
     // Booleans (`bool`)
@@ -13,7 +12,7 @@ fn main() {
         println!("Good morning!");
     }
 
-    let // Finish the rest of this line like the example! Or make it be false!
+    let is_evening = false;
     if is_evening {
         println!("Good evening!");
     }
diff --git a/exercises/primitive_types/primitive_types2.rs b/exercises/primitive_types/primitive_types2.rs
index f1616ed3b2..b9dc535815 100644
--- a/exercises/primitive_types/primitive_types2.rs
+++ b/exercises/primitive_types/primitive_types2.rs
@@ -3,7 +3,6 @@
 // Fill in the rest of the line that has code missing! No hints, there's no
 // tricks, just get used to typing these :)
 
-// I AM NOT DONE
 
 fn main() {
     // Characters (`char`)
@@ -19,7 +18,7 @@ fn main() {
         println!("Neither alphabetic nor numeric!");
     }
 
-    let // Finish this line like the example! What's your favorite character?
+    let your_character = '😻';
     // Try a letter, try a number, try a special character, try a character
     // from a different language than your own, try an emoji!
     if your_character.is_alphabetic() {
diff --git a/exercises/primitive_types/primitive_types3.rs b/exercises/primitive_types/primitive_types3.rs
index 8b0de44e96..cba0fc07da 100644
--- a/exercises/primitive_types/primitive_types3.rs
+++ b/exercises/primitive_types/primitive_types3.rs
@@ -5,10 +5,9 @@
 // Execute `rustlings hint primitive_types3` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 fn main() {
-    let a = ???
+    let a = [5; 100];
 
     if a.len() >= 100 {
         println!("Wow, that's a big array!");
diff --git a/exercises/primitive_types/primitive_types4.rs b/exercises/primitive_types/primitive_types4.rs
index d44d8776fa..9564c7a926 100644
--- a/exercises/primitive_types/primitive_types4.rs
+++ b/exercises/primitive_types/primitive_types4.rs
@@ -5,13 +5,12 @@
 // Execute `rustlings hint primitive_types4` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 #[test]
 fn slice_out_of_array() {
     let a = [1, 2, 3, 4, 5];
 
-    let nice_slice = ???
+    let nice_slice = &a[1..4];
 
     assert_eq!([2, 3, 4], nice_slice)
 }
diff --git a/exercises/primitive_types/primitive_types5.rs b/exercises/primitive_types/primitive_types5.rs
index f646986ea8..b6a99a587b 100644
--- a/exercises/primitive_types/primitive_types5.rs
+++ b/exercises/primitive_types/primitive_types5.rs
@@ -5,11 +5,10 @@
 // Execute `rustlings hint primitive_types5` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 fn main() {
     let cat = ("Furry McFurson", 3.5);
-    let /* your pattern here */ = cat;
+    let (name, age) = cat;
 
     println!("{} is {} years old.", name, age);
 }
diff --git a/exercises/primitive_types/primitive_types6.rs b/exercises/primitive_types/primitive_types6.rs
index 07cc46c65a..d556d085d3 100644
--- a/exercises/primitive_types/primitive_types6.rs
+++ b/exercises/primitive_types/primitive_types6.rs
@@ -6,13 +6,12 @@
 // Execute `rustlings hint primitive_types6` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
 
 #[test]
 fn indexing_tuple() {
     let numbers = (1, 2, 3);
     // Replace below ??? with the tuple indexing syntax.
-    let second = ???;
+    let second = numbers.1;
 
     assert_eq!(2, second,
         "This is not the 2nd number in the tuple!")
diff --git a/exercises/quiz1.rs b/exercises/quiz1.rs
index 4ee5ada7d8..6e7a9b3dcd 100644
--- a/exercises/quiz1.rs
+++ b/exercises/quiz1.rs
@@ -13,10 +13,11 @@
 //
 // No hints this time ;)
 
-// I AM NOT DONE
 
 // Put your function here!
-// fn calculate_price_of_apples {
+fn calculate_price_of_apples(apples: usize) -> usize {
+    if apples <= 40 { apples * 2 } else { apples }
+}
 
 // Don't modify this function!
 #[test]
diff --git a/exercises/quiz2.rs b/exercises/quiz2.rs
index 29925cafcd..f25d20d5e9 100644
--- a/exercises/quiz2.rs
+++ b/exercises/quiz2.rs
@@ -20,7 +20,6 @@
 //
 // No hints this time!
 
-// I AM NOT DONE
 
 pub enum Command {
     Uppercase,
@@ -32,11 +31,22 @@ mod my_module {
     use super::Command;
 
     // TODO: Complete the function signature!
-    pub fn transformer(input: ???) -> ??? {
+    pub fn transformer(input: Vec<(String, Command)>) -> Vec<String> {
         // TODO: Complete the output declaration!
-        let mut output: ??? = vec![];
+        let mut output: Vec<String> = vec![];
         for (string, command) in input.iter() {
             // TODO: Complete the function body. You can do it!
+            match command {
+                Command::Uppercase => output.push(string.to_uppercase()),
+                Command::Trim => output.push(string.trim().to_string()),
+                Command::Append(i) =>{
+                    let mut string = string.to_string();
+                    for foo in 0..*i {
+                        string += "bar";
+                    } 
+                    output.push(string)
+                },
+            }
         }
         output
     }
@@ -45,7 +55,7 @@ mod my_module {
 #[cfg(test)]
 mod tests {
     // TODO: What do we need to import to have `transformer` in scope?
-    use ???;
+    use crate::my_module::transformer;
     use super::Command;
 
     #[test]
diff --git a/exercises/quiz3.rs b/exercises/quiz3.rs
index 3b01d31320..62d4872a90 100644
--- a/exercises/quiz3.rs
+++ b/exercises/quiz3.rs
@@ -16,15 +16,15 @@
 //
 // Execute `rustlings hint quiz3` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
+use std::fmt::Display;
 
-pub struct ReportCard {
-    pub grade: f32,
+pub struct ReportCard<T> {
+    pub grade: T,
     pub student_name: String,
     pub student_age: u8,
 }
 
-impl ReportCard {
+impl <T: Display> ReportCard<T> {
     pub fn print(&self) -> String {
         format!("{} ({}) - achieved a grade of {}",
             &self.student_name, &self.student_age, &self.grade)
@@ -52,7 +52,7 @@ mod tests {
     fn generate_alphabetic_report_card() {
         // TODO: Make sure to change the grade here after you finish the exercise.
         let report_card = ReportCard {
-            grade: 2.1,
+            grade: "A+",
             student_name: "Gary Plotter".to_string(),
             student_age: 11,
         };
diff --git a/exercises/strings/strings1.rs b/exercises/strings/strings1.rs
index f50e1fa988..5d48b91b54 100644
--- a/exercises/strings/strings1.rs
+++ b/exercises/strings/strings1.rs
@@ -5,7 +5,6 @@
 // Execute `rustlings hint strings1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
     let answer = current_favorite_color();
@@ -13,5 +12,5 @@ fn main() {
 }
 
 fn current_favorite_color() -> String {
-    "blue"
+    "blue".to_string()
 }
diff --git a/exercises/strings/strings2.rs b/exercises/strings/strings2.rs
index 4d95d16a16..10f0a73f2c 100644
--- a/exercises/strings/strings2.rs
+++ b/exercises/strings/strings2.rs
@@ -5,11 +5,10 @@
 // Execute `rustlings hint strings2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
     let word = String::from("green"); // Try not changing this line :)
-    if is_a_color_word(word) {
+    if is_a_color_word(&word) {
         println!("That is a color word I know!");
     } else {
         println!("That is not a color word I know.");
diff --git a/exercises/strings/strings3.rs b/exercises/strings/strings3.rs
index b29f9325bc..9438c66f45 100644
--- a/exercises/strings/strings3.rs
+++ b/exercises/strings/strings3.rs
@@ -3,21 +3,20 @@
 // Execute `rustlings hint strings3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn trim_me(input: &str) -> String {
     // TODO: Remove whitespace from both ends of a string!
-    ???
+    input.trim().to_string()
 }
 
 fn compose_me(input: &str) -> String {
     // TODO: Add " world!" to the string! There's multiple ways to do this!
-    ???
+    input.to_string() + " world!"
 }
 
 fn replace_me(input: &str) -> String {
     // TODO: Replace "cars" in the string with "balloons"!
-    ???
+    input.replace("cars", "balloons")
 }
 
 #[cfg(test)]
diff --git a/exercises/strings/strings4.rs b/exercises/strings/strings4.rs
index e8c54acc55..d603c3c285 100644
--- a/exercises/strings/strings4.rs
+++ b/exercises/strings/strings4.rs
@@ -7,7 +7,6 @@
 //
 // No hints this time!
 
-// I AM NOT DONE
 
 fn string_slice(arg: &str) {
     println!("{}", arg);
@@ -17,14 +16,14 @@ fn string(arg: String) {
 }
 
 fn main() {
-    ???("blue");
-    ???("red".to_string());
-    ???(String::from("hi"));
-    ???("rust is fun!".to_owned());
-    ???("nice weather".into());
-    ???(format!("Interpolation {}", "Station"));
-    ???(&String::from("abc")[0..1]);
-    ???("  hello there ".trim());
-    ???("Happy Monday!".to_string().replace("Mon", "Tues"));
-    ???("mY sHiFt KeY iS sTiCkY".to_lowercase());
+    string_slice("blue");
+    string("red".to_string());
+    string(String::from("hi"));
+    string("rust is fun!".to_owned());
+    string_slice("nice weather".into());
+    string(format!("Interpolation {}", "Station"));
+    string_slice(&String::from("abc")[0..1]);
+    string_slice("  hello there ".trim());
+    string("Happy Monday!".to_string().replace("Mon", "Tues"));
+    string("mY sHiFt KeY iS sTiCkY".to_lowercase());
 }
diff --git a/exercises/structs/structs1.rs b/exercises/structs/structs1.rs
index 5fa5821c5b..d872efe4e7 100644
--- a/exercises/structs/structs1.rs
+++ b/exercises/structs/structs1.rs
@@ -5,13 +5,14 @@
 // Execute `rustlings hint structs1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 struct ColorClassicStruct {
-    // TODO: Something goes here
+    red: i32,
+    green: i32,
+    blue: i32,
 }
 
-struct ColorTupleStruct(/* TODO: Something goes here */);
+struct ColorTupleStruct(i32, i32, i32);
 
 #[derive(Debug)]
 struct UnitLikeStruct;
@@ -23,7 +24,10 @@ mod tests {
     #[test]
     fn classic_c_structs() {
         // TODO: Instantiate a classic c struct!
-        // let green =
+        let green = ColorClassicStruct{
+            red: 0,
+            green: 255,
+            blue: 0};
 
         assert_eq!(green.red, 0);
         assert_eq!(green.green, 255);
@@ -33,7 +37,7 @@ mod tests {
     #[test]
     fn tuple_structs() {
         // TODO: Instantiate a tuple struct!
-        // let green =
+        let green = ColorTupleStruct(0, 255, 0);
 
         assert_eq!(green.0, 0);
         assert_eq!(green.1, 255);
@@ -43,7 +47,7 @@ mod tests {
     #[test]
     fn unit_structs() {
         // TODO: Instantiate a unit-like struct!
-        // let unit_like_struct =
+        let unit_like_struct = UnitLikeStruct;
         let message = format!("{:?}s are fun!", unit_like_struct);
 
         assert_eq!(message, "UnitLikeStructs are fun!");
diff --git a/exercises/structs/structs2.rs b/exercises/structs/structs2.rs
index 328567f03a..a3b827d2d3 100644
--- a/exercises/structs/structs2.rs
+++ b/exercises/structs/structs2.rs
@@ -5,7 +5,6 @@
 // Execute `rustlings hint structs2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 #[derive(Debug)]
 struct Order {
@@ -38,7 +37,11 @@ mod tests {
     fn your_order() {
         let order_template = create_order_template();
         // TODO: Create your own order using the update syntax and template above!
-        // let your_order =
+        let your_order = Order {
+            name: String::from("Hacker in Rust"),
+            count: 1,
+            ..order_template
+        };
         assert_eq!(your_order.name, "Hacker in Rust");
         assert_eq!(your_order.year, order_template.year);
         assert_eq!(your_order.made_by_phone, order_template.made_by_phone);
diff --git a/exercises/structs/structs3.rs b/exercises/structs/structs3.rs
index 7cda5af103..40ce440df2 100644
--- a/exercises/structs/structs3.rs
+++ b/exercises/structs/structs3.rs
@@ -7,7 +7,6 @@
 // Execute `rustlings hint structs3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 #[derive(Debug)]
 struct Package {
@@ -31,12 +30,14 @@ impl Package {
         }
     }
 
-    fn is_international(&self) -> ??? {
-        // Something goes here...
+    fn is_international(&self) -> bool {
+        if self.sender_country != self.recipient_country{
+           true 
+        } else { false }
     }
 
-    fn get_fees(&self, cents_per_gram: u32) -> ??? {
-        // Something goes here...
+    fn get_fees(&self, cents_per_gram: u32) -> u32 {
+        self.weight_in_grams * cents_per_gram
     }
 }
 
diff --git a/exercises/tests/tests1.rs b/exercises/tests/tests1.rs
index 810277ac3d..a4808c5f05 100644
--- a/exercises/tests/tests1.rs
+++ b/exercises/tests/tests1.rs
@@ -10,12 +10,11 @@
 // Execute `rustlings hint tests1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 #[cfg(test)]
 mod tests {
     #[test]
     fn you_can_assert() {
-        assert!();
+        assert!(true);
     }
 }
diff --git a/exercises/tests/tests2.rs b/exercises/tests/tests2.rs
index f8024e9f22..d93ea05dac 100644
--- a/exercises/tests/tests2.rs
+++ b/exercises/tests/tests2.rs
@@ -6,12 +6,11 @@
 // Execute `rustlings hint tests2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 #[cfg(test)]
 mod tests {
     #[test]
     fn you_can_assert_eq() {
-        assert_eq!();
+        assert_eq!(1,1);
     }
 }
diff --git a/exercises/tests/tests3.rs b/exercises/tests/tests3.rs
index 4013e38415..50b849b60b 100644
--- a/exercises/tests/tests3.rs
+++ b/exercises/tests/tests3.rs
@@ -7,7 +7,6 @@
 // Execute `rustlings hint tests3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 pub fn is_even(num: i32) -> bool {
     num % 2 == 0
@@ -19,11 +18,11 @@ mod tests {
 
     #[test]
     fn is_true_when_even() {
-        assert!();
+        assert!(is_even(2));
     }
 
     #[test]
     fn is_false_when_odd() {
-        assert!();
+        assert!(!is_even(5));
     }
 }
diff --git a/exercises/tests/tests4.rs b/exercises/tests/tests4.rs
index 935d0db173..7c11a599d6 100644
--- a/exercises/tests/tests4.rs
+++ b/exercises/tests/tests4.rs
@@ -5,7 +5,6 @@
 // Execute `rustlings hint tests4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 struct Rectangle {
     width: i32,
@@ -30,17 +29,19 @@ mod tests {
     fn correct_width_and_height() {
         // This test should check if the rectangle is the size that we pass into its constructor
         let rect = Rectangle::new(10, 20);
-        assert_eq!(???, 10); // check width
-        assert_eq!(???, 20); // check height
+        assert_eq!(rect.width, 10); // check width
+        assert_eq!(rect.height, 20); // check height
     }
 
     #[test]
+    #[should_panic]
     fn negative_width() {
         // This test should check if program panics when we try to create rectangle with negative width
         let _rect = Rectangle::new(-10, 10);
     }
 
     #[test]
+    #[should_panic]
     fn negative_height() {
         // This test should check if program panics when we try to create rectangle with negative height
         let _rect = Rectangle::new(10, -10);
diff --git a/exercises/traits/traits1.rs b/exercises/traits/traits1.rs
index 37dfcbfe85..361a14785d 100644
--- a/exercises/traits/traits1.rs
+++ b/exercises/traits/traits1.rs
@@ -7,7 +7,6 @@
 // Execute `rustlings hint traits1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 trait AppendBar {
     fn append_bar(self) -> Self;
@@ -15,6 +14,9 @@ trait AppendBar {
 
 impl AppendBar for String {
     // TODO: Implement `AppendBar` for type `String`.
+    fn append_bar(self) -> Self {
+        format!("{self}Bar")
+    }
 }
 
 fn main() {
diff --git a/exercises/traits/traits2.rs b/exercises/traits/traits2.rs
index 3e35f8e11b..2908137195 100644
--- a/exercises/traits/traits2.rs
+++ b/exercises/traits/traits2.rs
@@ -8,13 +8,18 @@
 //
 // Execute `rustlings hint traits2` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
 
 trait AppendBar {
     fn append_bar(self) -> Self;
 }
 
 // TODO: Implement trait `AppendBar` for a vector of strings.
+impl AppendBar for Vec<String> {
+    fn append_bar(mut self) -> Self {
+        self.push("Bar".to_string());
+        self
+    }
+}
 
 #[cfg(test)]
 mod tests {
diff --git a/exercises/traits/traits3.rs b/exercises/traits/traits3.rs
index 4e2b06b0e5..0008d51122 100644
--- a/exercises/traits/traits3.rs
+++ b/exercises/traits/traits3.rs
@@ -8,10 +8,11 @@
 // Execute `rustlings hint traits3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 pub trait Licensed {
-    fn licensing_info(&self) -> String;
+    fn licensing_info(&self) -> String{
+        format!("Some information")
+    }
 }
 
 struct SomeSoftware {
diff --git a/exercises/traits/traits4.rs b/exercises/traits/traits4.rs
index 4bda3e571e..0df03936d6 100644
--- a/exercises/traits/traits4.rs
+++ b/exercises/traits/traits4.rs
@@ -7,7 +7,6 @@
 // Execute `rustlings hint traits4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 pub trait Licensed {
     fn licensing_info(&self) -> String {
@@ -23,7 +22,7 @@ impl Licensed for SomeSoftware {}
 impl Licensed for OtherSoftware {}
 
 // YOU MAY ONLY CHANGE THE NEXT LINE
-fn compare_license_types(software: ??, software_two: ??) -> bool {
+fn compare_license_types <T: Licensed, U: Licensed>(software: T, software_two: U) -> bool {
     software.licensing_info() == software_two.licensing_info()
 }
 
diff --git a/exercises/traits/traits5.rs b/exercises/traits/traits5.rs
index df1838054a..bb3a462d97 100644
--- a/exercises/traits/traits5.rs
+++ b/exercises/traits/traits5.rs
@@ -7,7 +7,6 @@
 // Execute `rustlings hint traits5` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 pub trait SomeTrait {
     fn some_function(&self) -> bool {
@@ -30,7 +29,7 @@ impl SomeTrait for OtherStruct {}
 impl OtherTrait for OtherStruct {}
 
 // YOU MAY ONLY CHANGE THE NEXT LINE
-fn some_func(item: ??) -> bool {
+fn some_func<T: SomeTrait + OtherTrait>(item: T) -> bool {
     item.some_function() && item.other_function()
 }
 
diff --git a/exercises/variables/variables1.rs b/exercises/variables/variables1.rs
index b3e089a527..469fd4ef41 100644
--- a/exercises/variables/variables1.rs
+++ b/exercises/variables/variables1.rs
@@ -5,9 +5,8 @@
 // Execute `rustlings hint variables1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
-    x = 5;
+    let x = 5;
     println!("x has the value {}", x);
 }
diff --git a/exercises/variables/variables2.rs b/exercises/variables/variables2.rs
index e1c23edf7d..eb9a5472a0 100644
--- a/exercises/variables/variables2.rs
+++ b/exercises/variables/variables2.rs
@@ -3,10 +3,9 @@
 // Execute `rustlings hint variables2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
-    let x;
+    let x: isize = 10;
     if x == 10 {
         println!("x is ten!");
     } else {
diff --git a/exercises/variables/variables3.rs b/exercises/variables/variables3.rs
index 86bed419f4..c40cf3aa7c 100644
--- a/exercises/variables/variables3.rs
+++ b/exercises/variables/variables3.rs
@@ -3,9 +3,8 @@
 // Execute `rustlings hint variables3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
-    let x: i32;
+    let x: i32 = 1;
     println!("Number {}", x);
 }
diff --git a/exercises/variables/variables4.rs b/exercises/variables/variables4.rs
index 5394f39462..2d056da911 100644
--- a/exercises/variables/variables4.rs
+++ b/exercises/variables/variables4.rs
@@ -3,10 +3,9 @@
 // Execute `rustlings hint variables4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
-    let x = 3;
+    let mut x = 3;
     println!("Number {}", x);
     x = 5; // don't change this line
     println!("Number {}", x);
diff --git a/exercises/variables/variables5.rs b/exercises/variables/variables5.rs
index a29b38be8e..2a312acb58 100644
--- a/exercises/variables/variables5.rs
+++ b/exercises/variables/variables5.rs
@@ -3,11 +3,10 @@
 // Execute `rustlings hint variables5` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
     let number = "T-H-R-E-E"; // don't change this line
     println!("Spell a Number : {}", number);
-    number = 3; // don't rename this variable
+    let number = 3; // don't rename this variable
     println!("Number plus two is : {}", number + 2);
 }
diff --git a/exercises/variables/variables6.rs b/exercises/variables/variables6.rs
index 853183babc..8c71edf3cf 100644
--- a/exercises/variables/variables6.rs
+++ b/exercises/variables/variables6.rs
@@ -3,9 +3,8 @@
 // Execute `rustlings hint variables6` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
-const NUMBER = 3;
+const NUMBER: isize = 3;
 fn main() {
     println!("Number {}", NUMBER);
 }
diff --git a/exercises/vecs/vecs1.rs b/exercises/vecs/vecs1.rs
index 65b7a7f835..b6d25924d5 100644
--- a/exercises/vecs/vecs1.rs
+++ b/exercises/vecs/vecs1.rs
@@ -7,12 +7,10 @@
 //
 // Execute `rustlings hint vecs1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
 
 fn array_and_vec() -> ([i32; 4], Vec<i32>) {
     let a = [10, 20, 30, 40]; // a plain array
-    let v = // TODO: declare your vector here with the macro for vectors
-
+    let v: Vec<i32> = a.to_vec(); 
     (a, v)
 }
 
diff --git a/exercises/vecs/vecs2.rs b/exercises/vecs/vecs2.rs
index e92c970aab..07050427e2 100644
--- a/exercises/vecs/vecs2.rs
+++ b/exercises/vecs/vecs2.rs
@@ -7,13 +7,12 @@
 //
 // Execute `rustlings hint vecs2` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
 
 fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
     for element in v.iter_mut() {
         // TODO: Fill this up so that each element in the Vec `v` is
         // multiplied by 2.
-        ???
+        *element *= 2;
     }
 
     // At this point, `v` should be equal to [4, 8, 12, 16, 20].
@@ -24,7 +23,7 @@ fn vec_map(v: &Vec<i32>) -> Vec<i32> {
     v.iter().map(|element| {
         // TODO: Do the same thing as above - but instead of mutating the
         // Vec, you can just return the new number!
-        ???
+        2 * element
     }).collect()
 }