Who helps them do some housework?改为被动语态

问题描述:

Who helps them do some housework?改为被动语态
晕 2L 3L 谁对啊......

who are they helped to do some housework by?
上面答得我认为不对,首先句意没有by不通,其次改为被动不定式不能省略要加to
希望对你有帮助