Question 1: They hope that their band will become popular someday.

Question 2: Nam usually has a bath when he feels bored and tired.

Question 3: Katheryn always wears a white shirt, but today she is wearing a blue one.

Question 4: Cindy has been living in the city since she graduated from university.

Question 5: I was studying while my father was working in the garden.

Question 6: I have not called Dan since he changed his phone number.

Question 7: After we paid for the meal, they gave us a voucher for the next one.

Question 8: My parents were painting the door when I visited them.

1. will become (Giải thích: hope that + S + will + V)

2. has (Giải thích:  'Nam' là chủ ngữ số ít, dùng has)

3. is wearing (Giải thích: có 'today' dùng Present continuous)

4. graduated (Giải thích: Present perfect + since + Past simple)

5. worked (Giải thích: hành động bố đang làm việc ngoài vườn là hành động xen ngang dùng Past simple)

6. has not called (Giải thích: có 'since' dùng Present perfect)

7. had paid (Giải thích: có 'after' và vế sau là Past simple, thì hành động phía trước phải ở thì Past perfect)

8. visited (Giải thích: ba má đang sơn cửa thì có hành động xen ngang dùng thì Past simple)