Update README.md

exercises/04-Call-a-function/README.md

@@ -4,7 +4,7 @@ tutorial: "https://www.youtube.com/watch?v=NU5iW_bWwmY"
 
 # `04` Calling a function  
 
-A function could receive 0 parameters, and you can it always returns something, event if you don't explicitly add the `return` statement.
+A function could receive zero parameters, and it always returns something, even if you don't explicitly add the `return` statement.
 
 :point_up: [Click here to read more about functions](https://content.breatheco.de/lesson/working-with-functions-python)
 
@@ -15,7 +15,7 @@ def calculate_area(length, edge):
     return length * edge
 ```
 
-If you want to use that function to calculate the area of a square with
+If you want to use that function to calculate the area of a square with:
 
 ```python
 length = 3
@@ -30,7 +30,7 @@ area = calculate_area(3,6)
 
 # 📝 Instructions:
 
-Create a new variables named square_area1, square_area2, square_area3 and call the function calculate_area 3 times one fo each square in the picture, for example: 
+Create a new variables named square_area1, square_area2, square_area3 and call the function calculate_area three times one for each square in the picture, for example: 
 
 ```python
 # For the first figure:
@@ -41,7 +41,7 @@ square_area1 = calculate_area(4,4)
 
 # 💡 Hint:
 
-Call the `calculate_area` function 3 times, one per each square, passing the length and edge of each square.
+Call the `calculate_area` function three times, one per each square, passing the length and edge of each square.
 
 :tv: [9 min video about functions in python](https://www.youtube.com/watch?v=NE97ylAnrz4)