70. Kind and kinds, sort and sorts etc.

 The words kind, sort, type and class are singular and should be used with this or that to modify a singular noun. 

The words kinds, sorts, types and classes are plural and should be used with these or those to modify plural nouns.

• Incorrect: I like these kind of mangoes.

 • Correct: I like these kinds of mangoes. 

• Incorrect: I don't like this sort of meat pies. 

• Correct: I don't like this sort of meat pie. 

• Incorrect: Those are the kinds of film I like to watch. 

• Correct: Those are the kinds of films I like to watch.

 • Incorrect: These type of cars are very fast. • Correct: These types of cars are very fast.