docs(vowel-dots): correct grammar

subjects/vowel-dots/README.md

@@ -2,9 +2,12 @@
 
 ### Instructions
 
-Create a function called vowelDots that receives a string and adds a `.` after
-every vowel ('y' is not considered a vowel here) using a regex called `vowels`.
+Create a function named `vowelDots` that receives a string. Your function should return a new string with a `.` after every vowel.
+
+Your RegEx should be stored in a variable named `vowels`.
+
+> a, e, i, o and u are considered as vowels here.
 
 ### Notions
 
-- [github.com/ziishaned/learn-regex#22-character-sets](https://github.com/ziishaned/learn-regex#22-character-sets)
+- [RegEx Character Sets](https://github.com/ziishaned/learn-regex#22-character-sets)