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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It is vital that we _____ act out at once to protect the environment.
#90531
A
would
B
should
C
will
D
can
—George, ___ _ you sing so loudly at such a late hour? —I am terribly sorry．
#87932
A
will
B
may
C
must
D
shall
．— Why didn’t you tell me the truth that day? — I _____, but you _____ for Fuzhou when I went to see you．
#88309
A
did; would leave
B
would; have left
C
would have; had left
D
had; left
Had I known her name，I________.
#86883
A
would invite her to lunch
B
would have invited her to lunch
C
invited her to lunch
D
could invite her to lunch
He ______ you more help even though he was very busy.
#86901
A
might have given
B
might give
C
may have given
D
may give