DK-1型制动机(电空位操作)“大闸”置过充位时()线得电。
A、803、809
B、803、805
C、807、806
D、806、808
参考答案:B
A.(A) When we are attending an English language course.
B.(B) When we are watching an interesting TV program.
C.(C) When we are enjoying the murmuring of a brook.
D.(D) When we are listening for a friend’s voice in a crowd.
文法等价的定义是什么?