诊断慢性阑尾炎,下列哪一项最重要
A.慢性右下腹隐痛史
B.有过典型的急性发作病史
C.右下腹有轻度压痛
D.X线钡餐检查阑尾炎未显影
E.排除阑尾炎以外疾病的可能
参考答案:D
在日常生活中,人们常说“开灯”、“关灯”,其物理含义是
A.开灯和关灯都是指闭合开关
B.开灯是指断开开关,关灯是指闭合开关
C.开灯和关灯都是指断开开关
D.开灯是指闭合开关,关灯是指断开开关
— Can you go swimming with us this afternoon?
— Sorry, I can't. I ______ take care of my little sister at home because my mother is ill. [ ]
A. can
B. may
C. must
D. would