Who ________ the bicycle?
A. invented
B. has invente
C. invents
D. had invented
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I was unhappy because the trip was cancelled. I ___________ forward to it.
A. was looking
B. am looking
C. has been looking
D. had been looking
I'm looking for Paul. _________ him?
A. did you see
B. have you seen
C. had you seen
D. were you see
Mary __________ for me when I ______
A. was waiting, arrived
B. has been waiting, arrived
C. has waited, arrived
D. was waiting, was arrived
A: __________ to the United States? B: No, never.
A. did you go
B. had you been
C. have you gone
D. have you been
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