根据首字母填空完成短文。

      Tell you a story. There w__________ some people in the boat. On the river, a man's sword fell i__________

the river, but he d__________ look for it. He made a m__________ on the bottom o__________ the boat. Soon

the boat c__________ the river. Then the man looked f__________ his sword under the mark on the boat, but

his sword w__________ there. Finally the people l__________ at the stupid m__________.

不属于公文的主体部分是（）

A．标题

B．作者

C．印章

D．正文