giúp e với ạ giải thích Exercise 3: Give the correct tenses (simple past or past continuous) 21. He (see) …………… a job advertisement on a local newspaper and (apply) …………….. for the job. 22. It was 5 p.m., and it (get) ……………………….. darker and darker. 23. I (not go) ………………… to school yesterday because (visit) …………………. my grandparents. 24. At this time last year, I (attend) …………………….. an English course. 25. I (write) ……………….. letters to my grandparents yesterday afternoon. 26. At 8 am yesterday, I (teach) ……………. at school and my wife (work) ……………… in her office. 27. We (walk) …………………. in the park when it (start) ……………………. to rain. 28. While I (talk) ………………….. to a friend, the teacher (ask) …………………. me a question. 29. We (sit) …………….. on a bench in the park when someone (take) ……………… our school bags. 30. We (lose) …………………. the keys while we (play) …………………. in the garden. 31. When the phone (ring) …………………, I (have) …………………… a bath. 32. What …………… you (do) ………………. when I (call) ………………… yesterday? 33. My sister and I (read) ……………… a comic book online when our father (come) …………….. in. 34. While they (sleep) …………………., the burglars (break) ………………………. into their house.