Without gravity, we _____ walk on the ground as freely as we do now. 
#63085
A
couldn’t
B
mustn’t
C
shan’t
D
needn’t
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The flowers in my room         every day, or they’ll die.
#75306
A
must water
B
must be watered
C
should water
D
can be watered
It ___________last night, for the ground is wet outside.
#63212
A
would be raining
B
would have rained
C
must rain
D
must have rained