17. They have to repair the engine of the car
18. My father is telling a funny story.
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The engine of the car has to be repaired....
19. The boy broke a vase of flowers yesterday
20. I was washing my clothes when you called.
21. They have taught math at this school for a long time.
22. They can repair all kinds of cars.
23. Did you buy this book at Nhan Van bookstore?
24. They haven't learned English for a long time.
25. Did her friends give her a lot of special presents?
26. I left my handbag on the bus this morning.
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27. We do a lot of homework every night.
28. What time does Mr. Green give his lecture?
29. We are going to paint our house tomorrow.
30. They will build a big hospital tomorrow.