1 We haven't seen each other for 5 years 

CT thì HTHT: S+have/has+PP+O

2 Mr Bill used to go swimming when he was young

CT used to: S+used to V+O

3 She is the best student in the class

CT so sánh nhất: S+be+the+ adj-est/most adj+N

4 How long does it take you to go to school everyday

How long+do/does+S+V?

1, We haven't seen each other for 5 years. (có for+tgian => dùng hiện tại hoàn thành)

2. Mr Bill used to go swimming when he was young (used to+Vinf: đã từng có thói quen làm gì)

3. She is the best student in her class. (dùng so sánh nhất)

4. How long does it take you to go to school everyday? (bạn tốn bao  nhiêu tgian để đến trường mỗi ngày?)

CHÚC BẠN HỌC TỐT!