Messages ______ be changed from sound into electricity before they ______ be sent by radio.
#90077
A
must; will
B
have to; can
C
can; must
D
need; may
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— It’s ten years since I met you last time. I ________ you at all.—I wouldn’t have, either, if someone ________ you by name.
#87417
A
didn’t recognize; didn’t call
B
haven’t recognized; didn’t call
C
can’t recognize; had called
D
didn’t recognize; hadn’t called
He ______ the key, so we ______ into the office.
#88113
A
hadn’t left; can’t
B
didn’t leave; couldn’t have got
C
hadn’t left; couldn’t get
D
hasn’t left; couldn’t get
I__________ you somewhere before, but your name has escaped me_________.
#90025
A
must see;for a moment
B
must have seen; for a moment
C
must see;for the moment
D
must have seen; for the moment