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 ______.
#87593
A
ustn’t be
B
ay not be
C
an’t be
D
on’t be
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The headmaster suggested that a good preparation ________ ahead of time.
#87902
A
must be made
B
should be made
C
will be made
D
can be made
To be on the safe side, we should fill up the tank now, because we ______ run out of gas on the way.
#90054
A
can
B
would
C
might
D
should
He ________ get into his own house because he has lost his keys.
#88359
A
mustn’t
B
doesn’t have to
C
can’t
D
needn’t
He the job well, but he so careless.
#89972
A
had done; had been
B
could do; was
C
could have done; was
D
hadn’t done; had been
—But for your timely warning, we _________ into great trouble. —Well, you know we’re friends.
#87527
A
would get
B
must have got
C
would have got
D
can have got