6. They won the medal at last, which delighted the school.

-> which (mệnh đề quan hệ chỉ vật)

-> hay dùng để thay thế cả mệnh đề

….N (thing) + which + V + O

….N (thing) + which + S + V

7. Lan used to go to school on foot months ago but now she doesn't

8. Tim used to play tennis

Used to/ use to + V1 : đã từng

1. They won the medal at last, which delighted the school.

- Sử dụng Đại từ quan hệ 'which'

2. Lan used to go to school on foot months ago but now she doesn't.

- Cấu trúc used to V: Từng, đã từng làm gì 

3. Timmy used to play tennis.

Cấu trúc used to V
=don't/doesn't + V any more/any longer
=no longer+ V(s/es)
=no longer+ do/does+S+V
=had a habit of+V-ing