"上消化道"指的是()
A.食管全程
B.食管+胃
C.食管+胃+十二指肠
D.食管+胃+十二指肠+空肠
E.食管+胃+十二指肠+空肠+回肠
参考答案:C
—Were you at home at 9:00 last night? I called you but nobody answered.
—Sorry, I ________ at that time.
A.take a shower
B.took a shower
C.was taking a shower
D.am taking a shower
轨道一般是指路基面以上的线路部分,由钢轨、()、道床、道岔等所组成。
A、隧道
B、排水沟
C、轨枕
D、警冲标