It is strange that such a thing ___ in your school.
A. will happen
B. happens
C. should happen
D. happened
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It is imperative that you ___ on time.
A. are
B. will be
C. be
D. would be
It is time we ___ up our results.
A. sum
B. summed
C. will sum
D. would sum
If the doctor had been available, the child ___.
A. would not die
B. would not have died
C. could not die
D. could not have died
Dr. Bethune worked hard as if he ___.
A. never had felt tired
B. had never felt tired
C. never felt tired
D. was tired never
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