尿毒症患者特征性表现是（）
A.恶心呕吐
B.手足搐搦
C.呼气有氨味
D.心包摩擦音
E.鼻衄
参考答案：D
Cars cause most of Beijing's air pollution. So the "No Car Day"campaign (活动) asks Beijing drivers
_____ their cars at home one day each month.[ ]
A. leave
B. leaving
C. to leave
D. to be left
一度电可以供“220V 20W’的电灯正常工作（ ）
A．50h
B．100h
C．30h
D．220h
