_____ the decision (决定) is so hard.[ ]
A. Makes
B. Make
C. Made
D. Making
答案:D
心房颤动最常见于
A.冠心病
B.风心病二尖瓣狭窄
C.高心病
D.甲亢性心脏病
E.缩窄性心包炎
试述注意的功能?