Ex 2: 
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 not flown to Singapore for 5 years.
4. I haven't had my hair cut since November.
5. We haven't called each other for 5 months.
6. We haven't met for a long time
7. How long have you had it?
8. I have never had such a delicious meal.
9. The last time I saw him was 8 days ago
10. It is 3 days since I last took a bath.
Ex 3:
1. cutted => cut
2. working => worked
3. haven't => hasn't
4. eat => eaten
5. bỏ still
6. câu này có sai ko nhỉ :((
7. since => for
8. since => for
9. for => since
10. hasn't => haven't

Ex 2: 
1. She hasn't been hometown for 4 years.
2. He has been working as a bank clerk for 3 months.
3.We have not been to Singapore for 5 years.
4. I haven't had my hair cut since November.
5. We haven't called each other for 5 months.
6. We haven't met for a long time
7. How long have you had it?
8. I have never had such a delicious meal.
9. The last time I saw him was 8 days ago
10. It is 3 days since I last took a bath.
Ex 3:
1. cutted => cut
2. working => worked
3. haven't => hasn't
4. eat => eaten
5. bỏ still
6. hình như câu này đúng rồi
7. since => for
8. since => for
9. for => since
10. hasn't => haven't

chúc bạn học tốt 

cho mình câu trả lời hay nhất nha