Sorry I didn't hear the ring. I in the kitchen when you phoned.
A. must have been
B. must be
C. can be
D. could have been
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You her in her office last Friday; she's been out of town for two weeks.
A. needn't have seen
B. must have seen
C. might have see
D. can't have seen
You can reuse those _________when you make your own jam this summer.
We have turned into a _______that produces a lot of garbage.
The unique _______of this car is its low emission.
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