Update 12_day_regular_expressions.md

typo at line 376. instead of "to" "ot" is written

12_Day_Regular_expressions/12_day_regular_expressions.md

@@ -373,7 +373,7 @@ console.log(matches)  // ["e-mail", "email", "Email", "E-mail"]
 
 ### Quantifier in RegExp
 
-We can specify the length of the substring we look for in a text, using a curly bracket. Let us see, how ot use RegExp quantifiers. Imagine, we are interested in substring that their length are 4 characters
+We can specify the length of the substring we look for in a text, using a curly bracket. Let us see, how to use RegExp quantifiers. Imagine, we are interested in substring that their length are 4 characters
 
 ```js
 const txt = 'This regular expression example was made in December 6,  2019.'