diff --git a/snippets/geometric_progression.md b/snippets/geometric_progression.md
index ca234f7d6..752768b86 100644
--- a/snippets/geometric_progression.md
+++ b/snippets/geometric_progression.md
@@ -13,8 +13,9 @@ Returns an error if `step` equals `1`.
 ```py
 from math import floor, log
 
-def geometric_progression(end, start = 1, step = 2):
-  return [start * step ** i for i in range(floor(log(end/start) / log(step)) + 1)]
+def geometric_progression(end, start=1, step=2):
+  return [start * step ** i for i in range(floor(log(end / start)
+          / log(step)) + 1)]
 ```
 
 ```py
diff --git a/snippets/group_by.md b/snippets/group_by.md
index 03b8c8184..b7e030243 100644
--- a/snippets/group_by.md
+++ b/snippets/group_by.md
@@ -5,9 +5,9 @@ tags: list,dictionary,intermediate
 
 Groups the elements of a list based on the given function.
 
-- Use `defaultdict()` to initialize a dictionary.
+- Use `collections.defaultdict` to initialize a dictionary.
 - Use `fn` in combination with a `for` loop and `dict.append()` to populate the dictionary.
-- Use the `dict()` constructor to convert it to a regular dictionary.
+- Use `dict()` to convert it to a regular dictionary.
 
 ```py
 from collections import defaultdict
@@ -21,6 +21,7 @@ def group_by(lst, fn):
 
 ```py
 from math import floor
+
 group_by([6.1, 4.2, 6.3], floor) # {4: [4.2], 6: [6.1, 6.3]}
 group_by(['one', 'two', 'three'], len) # {3: ['one', 'two'], 5: ['three']}
 ```
diff --git a/snippets/has_duplicates.md b/snippets/has_duplicates.md
index be8a1e8e6..a088344de 100644
--- a/snippets/has_duplicates.md
+++ b/snippets/has_duplicates.md
@@ -3,7 +3,7 @@ title: has_duplicates
 tags: list,beginner
 ---
 
-Returns `True` if there are duplicate values in a flat list, `False` otherwise.
+Checks if there are duplicate values in a flat list.
 
 - Use `set()` on the given list to remove duplicates, compare its length with the length of the list.
 
diff --git a/snippets/have_same_contents.md b/snippets/have_same_contents.md
index a188a8e31..16d352926 100644
--- a/snippets/have_same_contents.md
+++ b/snippets/have_same_contents.md
@@ -3,7 +3,7 @@ title: have_same_contents
 tags: list,intermediate
 ---
 
-Returns `True` if two lists contain the same elements regardless of order, `False` otherwise.
+Checks if two lists contain the same elements regardless of order.
 
 - Use `set()` on the combination of both lists to find the unique values.
 - Iterate over them with a `for` loop comparing the `count()` of each unique value in each list.
diff --git a/snippets/includes_all.md b/snippets/includes_all.md
index 80a6e14fe..f102f423f 100644
--- a/snippets/includes_all.md
+++ b/snippets/includes_all.md
@@ -3,9 +3,10 @@ title: includes_all
 tags: list,intermediate
 ---
 
-Returns `True` if all the elements in `values` are included in `lst`, `False` otherwise.
+Checks if all the elements in `values` are included in `lst`.
 
-- Check if every value in `values` is contained in `lst` using a `for` loop, returning `False` if any one value is not found, `True` otherwise.
+- Check if every value in `values` is contained in `lst` using a `for` loop.
+- Return `False` if any one value is not found, `True` otherwise.
 
 ```py
 def includes_all(lst, values):
diff --git a/snippets/includes_any.md b/snippets/includes_any.md
index 5f14d66e1..aef0d8e9d 100644
--- a/snippets/includes_any.md
+++ b/snippets/includes_any.md
@@ -3,9 +3,10 @@ title: includes_any
 tags: list,intermediate
 ---
 
-Returns `True` if any element in `values` is included in `lst`, `False` otherwise.
+Checks if any element in `values` is included in `lst`.
 
-- Check if any value in `values` is contained in `lst` using a `for` loop, returning `True` if any one value is found, `False` otherwise.
+- Check if any value in `values` is contained in `lst` using a `for` loop.
+- Return `True` if any one value is found, `False` otherwise.
 
 ```py
 def includes_any(lst, values):
diff --git a/snippets/initial.md b/snippets/initial.md
index 41c3cc373..2afa69374 100644
--- a/snippets/initial.md
+++ b/snippets/initial.md
@@ -13,5 +13,5 @@ def initial(lst):
 ```
 
 ```py
-initial([1, 2, 3]) # [1,2]
+initial([1, 2, 3]) # [1, 2]
 ```
diff --git a/snippets/initialize_2d_list.md b/snippets/initialize_2d_list.md
index c7941c72f..a98aac79d 100644
--- a/snippets/initialize_2d_list.md
+++ b/snippets/initialize_2d_list.md
@@ -5,14 +5,14 @@ tags: list,intermediate
 
 Initializes a 2D list of given width and height and value.
 
-- Use list comprehension and `range()` to generate `h` rows where each is a list with length `h`, initialized with `val`.
-- If `val` is not provided, default to `None`.
+- Use a list comprehension and `range()` to generate `h` rows where each is a list with length `h`, initialized with `val`.
+- Omit the last argument, `val`, to set the default value to `None`.
 
 ```py
-def initialize_2d_list(w,h, val = None):
+def initialize_2d_list(w, h, val = None):
   return [[val for x in range(w)] for y in range(h)]
 ```
 
 ```py
-initialize_2d_list(2, 2, 0) # [[0,0], [0,0]]
+initialize_2d_list(2, 2, 0) # [[0, 0], [0, 0]]
 ```
diff --git a/snippets/initialize_list_with_range.md b/snippets/initialize_list_with_range.md
index 41959f78f..f126a41f5 100644
--- a/snippets/initialize_list_with_range.md
+++ b/snippets/initialize_list_with_range.md
@@ -5,12 +5,12 @@ tags: list,beginner
 
 Initializes a list containing the numbers in the specified range where `start` and `end` are inclusive with their common difference `step`.
 
-- Use `list` and `range()` to generate a list of the appropriate length, filled with the desired values in the given range.
+- Use `list()` and `range()` to generate a list of the appropriate length, filled with the desired values in the given range.
 - Omit `start` to use the default value of `0`.
 - Omit `step` to use the default value of `1`.
 
 ```py
-def initialize_list_with_range(end, start=0, step=1):
+def initialize_list_with_range(end, start = 0, step = 1):
   return list(range(start, end + 1, step))
 ```
 
diff --git a/snippets/initialize_list_with_values.md b/snippets/initialize_list_with_values.md
index 07314a6c7..6fe5aab73 100644
--- a/snippets/initialize_list_with_values.md
+++ b/snippets/initialize_list_with_values.md
@@ -5,7 +5,7 @@ tags: list,beginner
 
 Initializes and fills a list with the specified value.
 
-- Use list comprehension and `range()` to generate a list of length equal to `n`, filled with the desired values.
+- Use a list comprehension and `range()` to generate a list of length equal to `n`, filled with the desired values.
 - Omit `val` to use the default value of `0`.
 
 ```py
diff --git a/snippets/intersection.md b/snippets/intersection.md
index 5ca26a174..5a1766023 100644
--- a/snippets/intersection.md
+++ b/snippets/intersection.md
@@ -5,7 +5,8 @@ tags: list,beginner
 
 Returns a list of elements that exist in both lists.
 
-- Create a `set` from `a` and `b`, then use the built-in set operator `&` to only keep values contained in both sets, then transform the `set` back into a `list`.
+- Create a `set` from `a` and `b`.
+- Use the built-in set operator `&` to only keep values contained in both sets, then transform the `set` back into a `list`.
 
 ```py
 def intersection(a, b):
diff --git a/snippets/intersection_by.md b/snippets/intersection_by.md
index 2a8ef7ad0..ceedde049 100644
--- a/snippets/intersection_by.md
+++ b/snippets/intersection_by.md
@@ -5,7 +5,8 @@ tags: list,function,intermediate
 
 Returns a list of elements that exist in both lists, after applying the provided function to each list element of both.
 
-- Create a `set` by applying `fn` to each element in `b`, then use list comprehension in combination with `fn` on `a` to only keep values contained in both lists.
+- Create a `set`, using `map()` to apply `fn` to each element in `b`.
+- Use a list comprehension in combination with `fn` on `a` to only keep values contained in both lists.
 
 ```py
 def intersection_by(a, b, fn):
@@ -15,5 +16,6 @@ def intersection_by(a, b, fn):
 
 ```py
 from math import floor
-intersection_by([2.1, 1.2], [2.3, 3.4],floor) # [2.1]
-```
\ No newline at end of file
+
+intersection_by([2.1, 1.2], [2.3, 3.4], floor) # [2.1]
+```
diff --git a/snippets/invert_dictionary.md b/snippets/invert_dictionary.md
index ac7f34f5d..e8c3a37aa 100644
--- a/snippets/invert_dictionary.md
+++ b/snippets/invert_dictionary.md
@@ -14,9 +14,9 @@ def invert_dictionary(obj):
 
 ```py
 ages = {
-  "Peter": 10,
-  "Isabel": 11,
-  "Anna": 9,
+  'Peter': 10,
+  'Isabel': 11,
+  'Anna': 9,
 }
-invert_dictionary(ages) # { 10: "Peter", 11 "Isabel", 9: "Anna" }
+invert_dictionary(ages) # { 10: 'Peter', 11: 'Isabel', 9: 'Anna' }
 ```
diff --git a/snippets/is_anagram.md b/snippets/is_anagram.md
index 55543f353..c84a38c1e 100644
--- a/snippets/is_anagram.md
+++ b/snippets/is_anagram.md
@@ -5,7 +5,7 @@ tags: string,intermediate
 
 Checks if a string is an anagram of another string (case-insensitive, ignores spaces, punctuation and special characters).
 
-- Use `isalnum()` to filter out non-alphanumeric characters, `lower()` to transform each character to lowercase.
+- Use `str.isalnum()` to filter out non-alphanumeric characters, `str.lower()` to transform each character to lowercase.
 - Use `collections.Counter` to count the resulting characters for each string and compare the results.
 
 ```py
@@ -20,5 +20,5 @@ def is_anagram(s1, s2):
 ```
 
 ```py
-is_anagram("#anagram", "Nag a ram!")  # True
+is_anagram('#anagram', 'Nag a ram!')  # True
 ```
diff --git a/snippets/is_contained_in.md b/snippets/is_contained_in.md
index 1ec234cb7..d19f9d244 100644
--- a/snippets/is_contained_in.md
+++ b/snippets/is_contained_in.md
@@ -3,9 +3,10 @@ title: is_contained_in
 tags: list,intermediate
 ---
 
-Returns `True` if the elements of the first list are contained in the second one regardless of order, `False` otherwise.
+Checks if the elements of the first list are contained in the second one regardless of order.
 
-- Use `count()` to check if any value in `a` has more occurences than it has in `b`, returning `False` if any such value is found, `True` otherwise.
+- Use `count()` to check if any value in `a` has more occurences than it has in `b`.
+- Return `False` if any such value is found, `True` otherwise.
 
 ```py
 def is_contained_in(a, b):
diff --git a/snippets/is_even.md b/snippets/is_even.md
index e5951808e..25f18bfd3 100644
--- a/snippets/is_even.md
+++ b/snippets/is_even.md
@@ -3,10 +3,10 @@ title: is_even
 tags: math,beginner
 ---
 
-Returns `True` if the given number is even, `False` otherwise.
+Checks if the given number is even.
 
-- Checks whether a number is odd or even using the modulo (`%`) operator.
-- Returns `True` if the number is even, `False` if the number is odd.
+- Check whether a number is odd or even using the modulo (`%`) operator.
+- Return `True` if the number is even, `False` if the number is odd.
 
 ```py
 def is_even(num):
diff --git a/snippets/is_odd.md b/snippets/is_odd.md
index ea199b423..0f6565f2e 100644
--- a/snippets/is_odd.md
+++ b/snippets/is_odd.md
@@ -3,7 +3,7 @@ title: is_odd
 tags: math,beginner
 ---
 
-Returns `True` if the given number is odd, `False` otherwise.
+Checks if the given number is odd.
 
 - Checks whether a number is even or odd using the modulo (`%`) operator.
 - Returns `True` if the number is odd, `False` if the number is even.
diff --git a/snippets/is_prime.md b/snippets/is_prime.md
index 29f8c3b96..1e2bf61e6 100644
--- a/snippets/is_prime.md
+++ b/snippets/is_prime.md
@@ -6,7 +6,8 @@ tags: math,intermediate
 Checks if the provided integer is a prime number.
 
 - Return `False` if the number is `0`, `1`, a negative number or a multiple of `2`.
-- Use `all()` and `range()` to check numbers from `3` to the square root of the given number, returning `True` if none divides the given number, `False` otherwise.
+- Use `all()` and `range()` to check numbers from `3` to the square root of the given number.
+- Return `True` if none divides the given number, `False` otherwise.
 
 ```py
 from math import sqrt
diff --git a/snippets/is_weekday.md b/snippets/is_weekday.md
index d20b587e4..da0b6b55e 100644
--- a/snippets/is_weekday.md
+++ b/snippets/is_weekday.md
@@ -19,6 +19,6 @@ def is_weekday(d = datetime.today()):
 ```py
 from datetime import date
 
-is_weekday(date(2020,10,25)) # False
-is_weekday(date(2020,10,28)) # True
+is_weekday(date(2020, 10, 25)) # False
+is_weekday(date(2020, 10, 28)) # True
 ```
diff --git a/snippets/is_weekend.md b/snippets/is_weekend.md
index f390693e5..8e7d0aa01 100644
--- a/snippets/is_weekend.md
+++ b/snippets/is_weekend.md
@@ -19,6 +19,6 @@ def is_weekend(d = datetime.today()):
 ```py
 from datetime import date
 
-is_weekend(date(2020,10,25)) # True
-is_weekend(date(2020,10,28)) # False
+is_weekend(date(2020, 10, 25)) # True
+is_weekend(date(2020, 10, 28)) # False
 ```
diff --git a/snippets/kebab.md b/snippets/kebab.md
index e9c7dcead..32caf503b 100644
--- a/snippets/kebab.md
+++ b/snippets/kebab.md
@@ -5,7 +5,9 @@ tags: string,regexp,intermediate
 
 Converts a string to kebab case.
 
-- Break the string into words and combine them adding `-` as a separator, using a regexp.
+- Use `re.sub()` to replace any `-` or `_` with a space, using the regexp `r"(_|-)+"`.
+- Use `re.sub()` to match all words in the string, `str.lower()` to lowercase them.
+- Finally, use `str.join()` to combine all word using `-` as the separator.
 
 ```py
 from re import sub
@@ -20,6 +22,7 @@ def kebab(s):
 ```py
 kebab('camelCase') # 'camel-case'
 kebab('some text') # 'some-text'
-kebab('some-mixed_string With spaces_underscores-and-hyphens') # 'some-mixed-string-with-spaces-underscores-and-hyphens'
-kebab('AllThe-small Things') # "all-the-small-things"
+kebab('some-mixed_string With spaces_underscores-and-hyphens')
+# 'some-mixed-string-with-spaces-underscores-and-hyphens'
+kebab('AllThe-small Things') # 'all-the-small-things'
 ```
diff --git a/snippets/keys_only.md b/snippets/keys_only.md
index a959f8872..f7c1c5fc2 100644
--- a/snippets/keys_only.md
+++ b/snippets/keys_only.md
@@ -3,7 +3,7 @@ title: keys_only
 tags: dictionary,list,beginner
 ---
 
-Returns a flat list of all the keys in a flat dictionary.
+Creates a flat list of all the keys in a flat dictionary.
 
 - Use `dict.keys()` to return the keys in the given dictionary.
 - Return a `list()` of the previous result.
@@ -15,9 +15,9 @@ def keys_only(flat_dict):
 
 ```py
 ages = {
-  "Peter": 10,
-  "Isabel": 11,
-  "Anna": 9,
+  'Peter': 10,
+  'Isabel': 11,
+  'Anna': 9,
 }
 keys_only(ages) # ['Peter', 'Isabel', 'Anna']
-```
\ No newline at end of file
+```
diff --git a/snippets/last.md b/snippets/last.md
index 8d6289598..c8bd073b9 100644
--- a/snippets/last.md
+++ b/snippets/last.md
@@ -5,7 +5,7 @@ tags: list,beginner
 
 Returns the last element in a list.
 
-- use `lst[-1]` to return the last element of the passed list.
+- Use `lst[-1]` to return the last element of the passed list.
 
 ```py
 def last(lst):
diff --git a/snippets/longest_item.md b/snippets/longest_item.md
index d5fe5401e..cf3ad527e 100644
--- a/snippets/longest_item.md
+++ b/snippets/longest_item.md
@@ -4,13 +4,13 @@ tags: list,string,intermediate
 ---
 
 Takes any number of iterable objects or objects with a length property and returns the longest one. 
-If multiple objects have the same length, the first one will be returned.
 
-- Use `max()` with `len` as the `key` to return the item with the greatest length.
+- Use `max()` with `len()` as the `key` to return the item with the greatest length.
+- If multiple objects have the same length, the first one will be returned.
 
 ```py
 def longest_item(*args):
-  return max(args, key=len)
+  return max(args, key = len)
 ```
 
 ```py