黏膜的鳞状细胞癌占口腔癌总数的

A．60％

B．50％

C．70％

D．80％

E．90％

用括号内所给单词的适当形式填空，共5分

小题1:What a            (please) it is for me to play the piano with you!

小题2:Mother asked the Greens to help          (they) to some pears.

小题3:Tim sings even          (badly) than before.

小题4:He felt          (true) sorry for what he said.

小题5:           (clean) work is to make our city clean.