前牙在正中合和前伸牙合均有早接触，应磨改
A．上牙牙尖
B．下牙牙尖
C．上牙舌面窝
D．下牙唇面
E．上牙舌斜面
参考答案：B
消化道衰竭的首发症状为（）
A.出血
B.腹泻
C.呕吐
D.便秘
E.食欲缺乏
—— Where ＿＿＿＿＿＿＿＿?
—— I got stuck in the heavy traffic, or I＿＿＿＿＿here earlier.
A．did you go； had arrived
B．are you； would come
C．were you; would come
D．have you been； would have been
