It is written clearly in the requirements that all passengers ______ check onto board 30 minutes before the plane takes off.
#87571
A
may
B
can
C
will
D
shall
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 It is strongly suggested that measures _____students to cheat in the exams.
#89428
A
be taken to prevent
B
be taken to forbid
C
are taken to prevent
D
are taken to forbid