4. The students ________ (read) the textbooks in the classroom when the teacher came in.
举一反三
- Thestudents ____________ (read) English when the teacher came in.
- We were cleaning the classroom _______ the teacher came in. A: when B: so C: but D: and
- The two students were quarreling with each other the teacher came in. A: when B: as C: while D: then
- Hardly _________ the bell _________ when the teacher came in.
- The classroom _______ cleaned before the teacher came in. A: was B: has been C: had D: had been