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 _____ sooner but I didn’t know that they were waiting for me .
#86796
A
had come
B
was coming
C
would come
D
would have come
My aunt _____ here by now, for she took the early bus.
#90176
A
must arrive
B
can arrive
C
may arrive
D
ought to have arrived
You can’t imagine that a well-behaved gentleman _____ be so rude to a lady.
#90510
A
might
B
need
C
should
D
would
—You were driving at 100 km an hour, sir.—But officer, I ________. My car can’t go more than 80.
#88144
A
may not have to
B
couldn’t have been
C
wouldn’t like to
D
needn’t to be