在开动转载机前,必须先开动()。
A.前溜
B.后溜
C.破碎机
D.采煤机
参考答案:C
The teacher told us _____ to the recorder and read the dialogue three times.
A.listen
B.listened
C.listening
D.to listen
数6.75比什么数多2.61?(列方程解)