The manager wants to know if they _________ our letter yet.
A. have answered
B. answered
C. will answer
D. has answered
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When he __________ all the newspapers, he'll go home.
A. will have sold
B. has sold
C. will sell
D. sell
This is the third time we ___________improvements in that equipment.
A. had made
B. have made
C. are making
D. is making
_______ four years since John left school.
A. They have been
B. It is
C. It was
D. It have been
By the time I left the school I __________ that course for ten years.
A. taught
B. have taught
C. had taught
D. teaches
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