1.John was too ill to go to school.

⇒ John wasn't healthy enough to go to school

2. Tom is not as tall as Peter.

⇒ Peter is taller than Tom

3. The player kicked the ball into the goal

⇒ The ball was kicked  into the goal by the player

4. Shall I sit here?

⇒ Do you mind if I sit here?

5. It is a contest in which participants have to cook rice

⇒ It is a rice-cooking contest

6. People play football all over the world.

⇒ Football is played all over the world

7. The front yard is too small to play soccer in.

⇒ The front yard isn’t small enough to play soccer in

8. She started to live in Hanoi 2 years ago.

⇒ She has lived in Hanoi for 2 years

9. He began to study English when he was young. (since)

⇒ He has studied English since he was young

=>

1. John wasn't well/healthy enough to go to school.

-> adj enough to V : đủ để

-> well (adj) : tốt, khỏe

2. Peter is taller than Tom.

-> so sánh hơn tính từ ngắn adj-er than

3. The ball was kicked into the goal by the player.

-> bị động QKĐ was/were V3/ed

4. Do you mind if I sit here?

-> do you mind if S Vs/es? : bạn có phiền...

5. It's a rice-cooking contest.

-> rice-cooking contest : cuộc thi nấu cơm

6. Football is played all over the world.

-> bị động HTĐ is/am/are V3/ed

7. The front yard isn't big enough to play soccer in.

-> adj enough to V : đủ...để

8. She has lived in Hanoi for 2 years.

-> chuyển QKĐ sang HTHT, S have/has V3/ed, for + khoảng thời gian

9. He has studied English since he was young.

-> chuyển QKĐ sang HTHT, S have/has V3/ed, since + mốc thời gian