左右心房的识别可根据()。
A.与肺静脉的连接
B.与腔静脉的连接
C.与肝脏的关系
D.声学造影
E.以上都是
参考答案:E
--- Learning a language isn’t easy. It takes time.
--- I agree. ______. There’s no short cut.
A.All roads lead to Rome
B.Rome wasn’t built in a day
C.Practice makes perfect
D.Slow but sure wins the race
日常使用的针式打印机为()针的。
A.7
B.18
C.9或24
D.48