--- How much shall I pay for the phone call? --- You ________. This is free of charge. 
#87096
A
shouldn’t
B
can’t
C
don’t have to
D
mustn’t
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They demanded that the books________ to the school library at once. 
#86780
A
return
B
should return
C
be returned
D
would be returned
She ____ the film. She knows nothing about it.
#86975
A
can’tsee
B
can’thaveseen
C
mustsee
D
mustn’thaveseen
 Look! That fellow is too sleepy to work. He ______ up reading until midnight.
#88455
A
mustn’t stay
B
mustn’t have stayed
C
ought not to stay
D
should not have stayed