Cấu trúc áp dụng:
When/ While + S1 + was/were + V-ing + O, S2+ V-ed2
=> diễn tả một sự việc đang xảy ra thì có một sự việc khác chen vào
While S1 + was/were + V-ing, S2 + was/were+ V-ing
=> diễn tả hai sự việc đang diễn ra tại cùng 1 thời điểm trong quá khứ
1, phoned (past simple tense); were playing (past continuous tense)
2, were playing; suddenly began
3, was working; were swimming
4, was waiting; saw
5, were taking out; gets
6, was putting one; was polishing
7, were you doing
8, listened; was explaining
9, was sitting; didn’t answer
10, was practicing; came
11, were doing; were lying
12, was filling; ran
13, saw; was still wearing
14, were dancing; broke
15, was driving; saw; was watching; stopped; got; was getting; ran; went; was getting; appeared; sitting; started; didn’t move; jumped; shouted; barked; started; followed; saw; were bleeding
16, was going; heard
17, saw; didn’t see; was looking
