小儿贫血的主要病理基础是()
A.先天禀赋不足
B.血虚不荣
C.后天喂养不当
D.他病伤脾
E.失血
参考答案:B
Great changes _____ in our hometown since 1985.[ ]
A. have happened
B. have taken place
C. have been happened
D. have been taken place
商业街区的重点覆盖区域为()。
A、步行街;
B、餐饮店铺;
C、办公区;
D、休息区。