地西泮（diazepam）不具有下列哪项作用（）
A.镇静抗焦虑
B.抗惊厥
C.缩短慢波睡眠时相
D.中枢性肌松驰作用
E.抗抑郁作用
参考答案：E
“3个7相加”写成加法算式是（ ），写成乘法算式是（ ）。
－Is that your chemistry teacher Miss. Zhang?
－It ______ be her. She has gone to Beijing for a trip. [ ]
A. must
B. can't
C. might
D. need
