Câu 3 và câu 4 trên cùng:
3. have moved/have lived
4. am going
Read the passage
1. Alexander Graham Bell was born in 1847 in Edinburgh, Scotland.
2. He worked with deaf-mutes at  Boston University.
3. Thomas Watson is Bell's assistant.
4. Yes, they did. 

1. Alexander Graham Bell was born in 1847 in Edinburgh, Scotland.
2. He worked with deaf-mutes at  Boston University.
3. Thomas Watson is Bell's assistant.
4. Yes, they did.