静脉补钾的浓度正确的是:()
A.0.3%
B.3%
C.0.5%
D.0.1%
E.0.4%
参考答案:A
The bus is _____________ than a plane. [ ]
A. cheap
B. cheaper
C. faster
什么是俗名,什么是学名,其构成如何?