The car is rather difficult __________.
A. to repair
B. to be repaired
C. repairing
D. being repaired
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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
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
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