题目内容：

we all feel it is jack as well as his wife that___for their son'sbad behavior at school.
为什么填is to blame 而不填is to be blamed?

优质解答

这是英语中主动形式表被动意义的问题
不定式to blame,to let用作表语时,通常要用主动表被动：
Who is to blame?该怪谁呢?
The house is to let.此屋出租.