Such writings are good for nothing_______ the naive, among whom they spread bad influences and foster bad habits.

A.except bluffed

B.except to bluff

C.but bluff

D.but to bluffed

   【答】表示“除了”的介词 but 和 except 后面的动词通常用带to 的不定式，如果前面有实义动词 do 的某种形式，可以省略 to , 所以，B.except to bluff 是答案。