Chia các động từ trong ngoặc ra thì simple past hoặc present perfect:
1) We (study)...............a very hard lesson the day before yesterday
2) We ( study)................................................almost every lesson in this book so far
3) We ( never/ watch)..........................that television program...........................
4) We (watch).....................an interesting program on television last night...............
5) My wife and I........................................( travel) by air many times in the past
6) My wife and I (travel).................................. to Mexico by air last summer
7) I (read)..................that novel by Hemingway sevaral times before.
8) I (read).........................that novel again during my last vacation.
9) I (have).........................a little trouble with my car last week.
10) However, I (have)......................... no trouble with my car since then.