带有to的不定式怎样变被动语态?

楼上说的对，但跟问题中的例句似乎关系不大。

ought to do中，to do并不是不定式，ought to 应看作一个整体，相当于一个情态动词，所以这个句子变不定式应按情态动词的变法：

can do --> can be done
ought to do --> ought to be done

People oughtn't to criticze her for this matter.
-->
She oughtn't to be criticized (by people) for this matter.

let/hear/see/make/watch这些词是不带to的动词不定式．let/hear/see/make/watch＋sb＋do/dong他们的不定式应该为：be＋不带to的动词的过去分词＋to＋do或者是be＋不带to的动词的过去分词＋doing．例如：Ilet him write． He is let to write.

记住to be done的真理