集中式供水的管道埋设时,应注意:饮用水管道与污水管平行时,水平距离不小于()
A.0.1m
B.0.4m
C.0.5m
D.1.0m
E.1.5m
参考答案:E
----The boy never has____breakfast.
----It’s___unhealthy habit.you must ask him to change it.
A./,an
B. the ,an
C./ ,a
D. the ,an
什么叫上位连接?