Nam is my classmates.
Correction: Nam is my classmate.

I think collecting stamps are interesting.
Correction: I think collecting stamps is interesting.

My dad cooks very good.
Correction: My dad cooks very well.

I enjoy to ride my bike to school.
Correction: I enjoy riding my bike to school.

We usually go in a small lake out of the city at weekends.
Correction: We usually go to a small lake out of the city at weekends.

Do you still play football next year?
Correction: Do you still plan to play football next year?

We like doing fishing because it is relaxing.
Correction: We like fishing because it is relaxing.

Do you think bird-watching interesting?
Correction: Do you think bird-watching is interesting? 
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