I _____________ English with him last weekend. [ ]
A. study
B. studying
C. studied
答案:C
戴全口义齿讲话和进食时上下牙有撞击声,是由于
A.排牙不准确B.下颌前伸C.下颌后退D.垂直距离过低E.垂直距离过高
胸骨后绞窄样痛并有重压窒息感,常见于()
A.急性心包炎
B.夹层动脉瘤
C.胸膜炎
D.肺梗死
E.心绞痛