1. You forgot to turn off the radio, didn't you ?
→ You didn't remember to turn off the radio, did you? ( câu hỏi đuôi)

2. Everyday thousands of trees are cut down in the world.
→ Everyday people cut down thousands of trees in the world.
3. "Have you done your homework?" asked the teacher.
→ The teacher asked me if I had done my homework. ( chuyển từ câu trực tiếp→gián tiếp)
4. The exercise was so easy that all students could do it.
→ It was such an easy exercise that all students could do it. (cấu trúc so that, such that)

5. I love to play tennis.
→ I enjoy playing tennis. ( chỉ có love/like/hate/prefer mới + cả toV/Ving thôi)

1. turn off the radio, did you?

2. cut down thousands of trees in the world.

3. if /whether I had done my homework.

4. an easy exercise that all students could do it. 

5. playing tennis.