1. The school will hold some marathon races for students this year

→ Some marathon races for students will be held by the school this year.

⇒ Cấu trúc passive: S + modal verb/be + Ved/V3 + by ... + (preposition) + (time)

2. You must clean the house; and then you can watch TV.

→ If you want to watch TV, you must clean the house.

⇒ Cấu trúc if loại 1: If + S + V1, S + modal verb/will + Vo

3. She visited her hometown. She was born and grew up there.

→ She visited her hometown where she was born and grew up.

⇒ Cấu trúc relative clause: vì là "hometown" nên dùng where và lược bỏ "there", không có giới từ phía sau nên không dùng which.