1. Nam started studying English 5 years ago
→ Nam has been learning English for 5 years so far
2. We started to play soccer an hour ago
→ We have been playing football for an hour now 
3. She started reading this novel a week ago
→ She has been reading this book for a week  
4. He started writing this book last year
→ He has been writing this book since last year 
5. My sister began playing badminton in 1986
→ My sister has been playing badminton since 19866.
Hoa began playing piano when she was ten
→ Hoa has been playing piano since she was ten.
7. Mr Hai began to be a doctor when he was 21
→ Mr Hai has been being a doctor since he was 21
8. Hung stopped playing soccer last year
→ Hung hasn’t been playing soccer since last year
9. I stopped smoking 2 years ago
→ I haven’t been smoking for 2 years 
10. She stopped writing when she moved to England
→ She hasn’t been writing since she moved to England
11. My brother stopped working in this factory last month
→ My brother hasn’t been working in this factory since last month.
12. Maria stopped planting flowers 10 years ago
→ Maria hasn’t been planting flowers for 10 years
13. Ba started building this hotel a year ago.
→ Ba has been building this hotel for a year
14. She stopped playing volleyball a year ago
→ She hasn’t been playing volleyball for a year
 

1. Nam started studying English 5 years ago.
   - **Nam has learned English for 5 years.**

2. We started to play soccer an hour ago.
   - **We have played soccer for an hour.**

3. She started reading this novel a week ago.
   - **She has been reading this novel for a week.**

4. He started writing this book last year.
   - **He has been writing this book since last year.**

5. My sister began playing badminton in 1986.
   - **My sister has played badminton since 1986.**

6. Hoa began playing the piano when she was ten.
   - **Hoa has been playing the piano since she was ten.**

7. Mr. Hai began to be a doctor when he was 21.
   - **Mr. Hai has been a doctor since he was 21.**

8. Hung stopped playing soccer last year.
   - **Hung hasn't played soccer since last year.**

9. I stopped smoking 2 years ago.
   - **I haven't smoked for 2 years.**

10. She stopped writing when she moved to England.
    - **She hasn't written since she moved to England.**

11. My brother stopped working in this factory last month.
    - **My brother hasn't worked in this factory since last month.**

12. Maria stopped planting flowers 10 years ago.
    - **Maria hasn't planted flowers for 10 years.**

13. Ba started building this hotel a year ago.
    - **Ba has been building this hotel for a year.**

14. She stopped playing volleyball a year ago.
    - **She hasn't played volleyball for a year.**

3. She started reading this novel a week ago.  
→ She has read this novel for a week.  
**Giải thích:** Câu này sử dụng thì hiện tại hoàn thành để diễn tả hành động bắt đầu trong quá khứ và vẫn tiếp tục đến hiện tại.

4. He started writing this book last year.  
→ He has written this book since last year.  
**Giải thích:** Câu này cũng sử dụng thì hiện tại hoàn thành để chỉ ra rằng việc viết sách bắt đầu từ năm ngoái và vẫn đang tiếp tục.

5. My sister began playing badminton in 1986.  
→ My sister has played badminton since 1986.  
**Giải thích:** Câu này cho thấy việc chơi cầu lông bắt đầu từ năm 1986 và vẫn tiếp tục đến hiện tại.

6. Hoa began playing piano when she was ten.  
→ Hoa has played the piano since she was ten.  
**Giải thích:** Câu này diễn tả rằng Hoa bắt đầu chơi piano từ khi cô ấy 10 tuổi và vẫn đang chơi.

7. Mr Hai began to be a doctor when he was 21.  
→ Mr Hai has been a doctor since he was 21.  
**Giải thích:** Câu này cho thấy Mr Hai bắt đầu làm bác sĩ từ khi 21 tuổi và vẫn đang làm bác sĩ.

8. Hung stopped playing soccer last year.  
→ Hung hasn't played soccer since last year.  
**Giải thích:** Câu này sử dụng thì hiện tại hoàn thành để diễn tả rằng Hung không còn chơi bóng đá từ năm ngoái.

9. I stopped smoking 2 years ago.  
→ I haven't smoked for 2 years.  
**Giải thích:** Câu này cho thấy việc không hút thuốc bắt đầu từ 2 năm trước và vẫn tiếp tục đến hiện tại.

10. She stopped writing when she moved to England.  
→ She hasn't written since she moved to England.  
**Giải thích:** Câu này diễn tả rằng cô ấy không còn viết từ khi chuyển đến Anh.

11. My brother stopped working in this factory last month.  
→ My brother hasn't worked in this factory since last month.  
**Giải thích:** Câu này cho thấy việc không làm việc ở nhà máy bắt đầu từ tháng trước và vẫn tiếp tục.

12. Maria stopped planting flowers 10 years ago.  
→ Maria hasn't planted flowers for 10 years.  
**Giải thích:** Câu này diễn tả rằng Maria không còn trồng hoa từ 10 năm trước.

13. Ba started building this hotel a year ago.  
→ Ba has built this hotel for a year.  
**Giải thích:** Câu này cho thấy Ba bắt đầu xây dựng khách sạn từ một năm trước và vẫn đang tiếp tục.

14. She stopped playing volleyball a year ago.  
→ She hasn't played volleyball for a year.  
**Giải thích:** Câu này diễn tả rằng cô ấy không còn chơi bóng chuyền từ một năm trước.

She has read this novel forr a week.
He has written this book since last year.
Ho has played piano since she was ten.