无意识的病人，造成呼吸道阻塞最常见的原因是（）
A.会厌部痉挛
B.异物吸入
C.气道狭窄
D.舌根后坠
E.痰液壅塞
参考答案：E
Ladies and gentlemen, now I will _______ the story where I left off the day before yesterday.
A．keep up
B．take up
C．keep on
D．go on
