they A. Are...doing Mrs Yen 15. English exercises? B. Do...doing C. Are...do 16. to the city? C. Is...going A. Is...go the students B. Does...going at the museum? 17. C. Do...arriving A. Are...arriving a farmer A. Is...waiting B. Are...arriveing 18. for Mr Quang? B. Does...waiting C. Is...wait 19. What the children with? A. are...play B. are...playing C. do...waiting to the airport? 20. Why A. is...driveing he C. is...driving B. are...driving the vegetables? B. is...takeing 21. Where the driver A. is...taking C. does...taking the farmer and the driver B. are... 22. What A. is...unloading unloading C. are...unload 23. Where the students C. are...sitting B. are...siting down? В. are...copу A. is...siting 24. What the children C. do...copying A. are...copying 25. What exercises the teacher A. are...correcting B. is...correcting C. is...correct