异位妊娠发病率约为()
A.1‰
B.5‰
C.1%
D.2%
E.5%
参考答案:C
With so much noise of the traffic, I couldn't________and do my research work. [ ]
A. put down
B. settle down
C. break down
D. take down
选择涂料时,亮度越高越好。