In our class, when the bell rang and the
题型:选择题
问题:
In our class, when the bell rang and the teacher closed his book, it was a ______ for everyone to stand up.
A.signal
B.chance
C.mark
D.measure
In our class, when the bell rang and the teacher closed his book, it was a ______ for everyone to stand up.
A.signal
B.chance
C.mark
D.measure