According to our school rules, students ________ not carry mobile phones when taking a exam. 
#62612
A
will
B
may
C
shall
D
need
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I looked everywhere for the book, but I ______find it
#76915
A
mustn’t
B
needn’t
C
may not
D
couldn’t
Hurry up, or you ______ catch the train. 
#62829
A
needn’t
B
mustn’t
C
can’t
D
shouldn’t