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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His appearance has changed so much that you _____ not recognize him.
#88194
A
must
B
need
C
may
D
ought
It ____ last night, for the ground is wet now.
#88954
A
might not have rained
B
must have rained
C
couldn't have rained
D
rained
If we ________ the other road, we might have arrived here in time for the meeting.
#86996
A
had taken
B
take
C
took
D
have taken
--The mistake_____, I had been more careful.---But you weren’t at that time.
#86594
A
might have avoided
B
would avoid
C
would be avoided
D
might have been avoided
I left very early last night, but I wish I _____ so early.
#89363
A
didn’t leave
B
hadn’t left
C
haven’t left
D
couldn’t leave