So far no life has been found outside the earth, but while some scientists are actively searching for living things in outer space, others firmly believe there ____ .
#88293
A
mustn’t be
B
may not be
C
can’t be
D
won’t be
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I was too careless.If only I ___ my car!
#89314
A
hadn't lost
B
would not have lost
C
didn't lose
D
haven’t lost
When I was you age, I dared to go out alone at night, ________ you?
#89219
A
dared
B
dare
C
did
D
didn’t
—Why aren’t they here yet?—They_____ the bus.
#89522
A
can have missed
B
must be late for
C
may have missed
D
might be late for
I told your friend how to get to the hotel, but perhaps I______have driven her here.
#87301
A
could
B
should
C
must
D
might
—What’s your feeling now? —I am terribly sorry. If only I here yesterday!
#87389
A
came
B
would have come
C
have come
D
had come