6. He was nowhere __________.a. to see b. to be seen c. seeing d. seen
A. to see
B. to be seen
C. seeing
D. seen
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The work __________ as soon as possible.
A. has done
B. has been doing
C. should be done
D. is being done
I think the dog__________ killed last night.
A. must have been
B. should be
C. ought to
D. had
The railway__________ now.
A. is built
B. being built
C. is building
D. is being built
It__________ about 20 years to build the pyramids.
A. has been taken
B. may have taken
C. has been taking
D. may take
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