图中共有多少个凸多边形？
解：14个。
_____ is known to us all is that the 2008 Olympic Games will take place in Beijing. [ ]
A. It
B. What
C. As
D. Which
医德修养要坚持（）
A.集体性
B.组织性
C.实践性
D.强制性
E.机动性
