She_____ answer my phone call yesterday.
A. doesn't
B. didn't
C. wasn't
第1题:
---Do you want a lift home?
---It’s very kind of you, but I have a much late in the office. I overslept this morning because my morning clock _______.
A. doesn’t go off
B. won’t gone
C. wasn’t going off
D. didn’t go on
第2题:
4. The meeting ______ begin ______ the last man came.
A. didn’t ;until
B. not; until
C. doesn’t; until
D. will; until
第3题:
若周期信号x(t)的周期为T,则其基波角频率为()。
A.2π/T
B.π/T
C.π/2T
D.1/T
第4题:
_________ she practice her violin yesterday? No, she _________.
A、Was, wasn’t
B、Did, didn’t
C、Was, didn’t
D、Did, wasn’t
第5题: