收缩时使杓状软骨向外、稍向上，使声带外展，声门变大的是（）。
A.环杓后肌
B.环杓侧肌和杓肌
C.环甲肌
D.甲杓肌
E.杓会厌肌
参考答案：A
The English in the future will be quite different from the English of today.
It is possible that some English words may ____ even completely. [ ]
A. die down
B. die out
C. die off
D. die of
KQ-150潜孔钻机行走机构导向托最大外径为（）mm。
A.510
B.511
C.512
