双面用闸板防喷器的闸板上下对称,但不可颠倒使用。
参考答案:错
He was elected ______ president of the company, and _____ news came , in fact, as ______ surprise. [ ]
A. a; the ; /
B. /; the ; a
C. a; /; the
D. the; the; a
If I ___ free tonight, I'll go to the cinema with you.
A.am
B.was
C.will be
D.be