Students  ______ remain in their seats until all the exam papers have been collected.
#87735
A
must
B
shall
C
may
D
can
推荐题目
The captain urged that the mission ______ before dark.
#88032
A
must be finished
B
be finished
C
ought to be finished
D
was finished
David did not regret saying what he did but felt that he     it differently.
#87310
A
could express
B
would express
C
could have expressed
D
must have expressed