diff --git a/12_Day/12_day_regular_expressions.md b/12_Day/12_day_regular_expressions.md
index 71f95f73..676085a5 100644
--- a/12_Day/12_day_regular_expressions.md
+++ b/12_Day/12_day_regular_expressions.md
@@ -350,7 +350,7 @@ Zero or many times. The pattern could may not occur or it can occur many times.
 
 const pattern = /[a].*/g  //. any character, + any character one or more times 
 const txt = 'Apple and banana are fruits'
-const matches = re.match(pattern)
+const matches = txt.match(pattern)
 
 console.log(matches)  // ['and banana are fruits']
 
@@ -383,7 +383,7 @@ console.log(matches)  // ['2019']
 
 ```js
 const txt = 'This regular expression example was made in December 6,  2019.'
-const regex_pattern = /\d{1, 4}/g   // 1 to 4
+const pattern = /\d{1,4}/g   // 1 to 4
 const matches = txt.match(pattern)
 console.log(matches)  // ['6', '2019']
 ```
@@ -396,7 +396,7 @@ console.log(matches)  // ['6', '2019']
 const txt = 'This regular expression example was made in December 6,  2019.'
 const pattern = /^This/ // ^ means starts with
 const matches = txt.match(pattern)
-console.log(matches)  / ['This']
+console.log(matches)  // ['This']
 ```
 
 - Negation
@@ -405,12 +405,12 @@ console.log(matches)  / ['This']
 const txt = 'This regular expression example was made in December 6,  2019.'
 const pattern = /[^A-Za-z,. ]+/g  // ^ in set character means negation, not A to Z, not a to z, no space, no coma no period
 const matches = txt.match(pattern)
-console.log(matches)  ["6", "2019"]
+console.log(matches)  // ["6", "2019"]
 ```
 
 ### Exact match
 
-It should hav ^ starting and $ which is an end.
+It should have ^ starting and $ which is an end.
 
 ```js
 let pattern = /^[A-Z][a-z]{3,12}$/;
diff --git a/15_Day/15_day_classes.md b/15_Day/15_day_classes.md
index e878e537..400d03d0 100644
--- a/15_Day/15_day_classes.md
+++ b/15_Day/15_day_classes.md
@@ -204,9 +204,10 @@ class Person {
 }
 
 const person1 = new Person() // it will take the default values
-const person1 = new Person('Lidiya', 'Tekle', 28, 'Finland', 'Espoo')
+const person2 = new Person('Lidiya', 'Tekle', 28, 'Finland', 'Espoo')
 
 console.log(person1)
+console.log(person2)
 ```
 
 ```sh
diff --git a/16_Day/16_day_json.md b/16_Day/16_day_json.md
index b4660016..ff04882d 100644
--- a/16_Day/16_day_json.md
+++ b/16_Day/16_day_json.md
@@ -327,8 +327,8 @@ const users = {
   }
 }
 
-const text = JSON.stringify(users, undefined, 4)
-console.log(text) // text means JSON- because json is a string form of an object.
+const txt = JSON.stringify(users, undefined, 4)
+console.log(txt) // text means JSON- because json is a string form of an object.
 ```
 
 ```sh
@@ -446,8 +446,8 @@ const user = {
   points: 30
 }
 
-const text = JSON.stringify(user,['firstName', 'lastName', 'country', 'city', 'age'],4)
-console.log(text)
+const txt = JSON.stringify(user,['firstName', 'lastName', 'country', 'city', 'age'],4)
+console.log(txt)
 ```
 
 ```sh
@@ -594,4 +594,4 @@ const text = `{
 
 🎉 CONGRATULATIONS ! 🎉
 
-[<< Day 15](https://github.com/Asabeneh/30DaysOfJavaScript/blob/master/15_Day/15_day_classes.md) | [Day 17 >>](https://github.com/Asabeneh/30DaysOfJavaScript/blob/master/17_Day/17_day_web_storage.md)
\ No newline at end of file
+[<< Day 15](https://github.com/Asabeneh/30DaysOfJavaScript/blob/master/15_Day/15_day_classes.md) | [Day 17 >>](https://github.com/Asabeneh/30DaysOfJavaScript/blob/master/17_Day/17_day_web_storage.md)