This is the third time we ___________improvements in that equipment.
A. had made
B. have made
C. are making
D. is making
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_______ 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
She asked the worker how long _______ to build the church.
A. it would take
B. had it taken
C. it takes
D. it had taken
Mary couldn't open the front door because she _______ the key.
A. had forgotten
B. was forgetting
C. has forgotten
D. forgot
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