“请让我来关心你，就像关心我自己；请让我来关心你，这世界会更美丽……”，这首歌词告诉我们，友谊会使世界变得更美丽。所以，我们应该[ ]

A．寻找友谊     

B．交换友谊   

C．珍视友谊        

D．炫耀友谊

He is not（）to understand the market situation.

A.so quick

B.quick enough

C.enough quick

D.as quick as