1. I do my duty
2. We do our homework
3. I do know him.
4. I’m doing my exam in a few weeks.
5. He does know how to play piano.
6. I need to do my homework now.
7. My friend does his best to win in the competition
8. I did lock the door
9. He does understand you.
10. Do you do exercises every day?
11. My mum likes to do shopping, but I don't
12. Do you know her? She is my big sister
13. Doing nothing seems to be her hobby.
14. May I help you to do the accounts?
а можно больше информации, чтобы решить это ?