Ex4

1. She hasn't come back to her hometown for 4 years.

2. He has been working as a bank clerk for 3 months

3. We have flown to Singapore for 5 years

4. I haven't had my hair cut since November.

5. We haven't called each other for five months.

6. We haven't met each other for a long time.

7. How long have you had it?

8. I have never had such a delicious meal before.

9. The last time I saw him was 8 days ago

10. It is four day since I last took a bath on Wednesday

Ex5

1. cutted=>cut

2. working=> worked

3. haven't=> hasn't

4. eat=> eaten

5. hasn't=> haven't

6.  next week=>bỏ(câu này khong chắc lắm, sai bạn thông cảm nhé)

7. since=> for