下列关于我国交通运输网密度的叙述，正确的是[ ]
A、全国分布均衡
B、东部地区大于西部地区
C、南部地区大于北部地区
D、北部地区大于南部地区
答案：B
He didn't tell his parents he was going home because he wanted to give them a . [ ]
A. joy
B. surprise
C. shock
D. happiness
《素问·宣明五气篇》指出：久卧伤（）。
A.气
B.血
C.筋
D.肉
