《上古天真论》“地道不通”指（）。
A.六腑气机不通
B.大便不通
C.月经停止来潮
D.三焦之道闭阻
E.以上均不是
参考答案：C
It's nice of you to ______ so much time showing me around your school. [ ]
A. take
B. spend
C. cost
D. have
结构模线
