The work must be finished by them tomorrow.被动语态的话就是指把动词后面的动词提前做主语，如果不是主语不是人（I, you, they等等）的话，那么就要用被动语态。这句话就是工作被完成。Don't take my English book aways without permittingwithout 后面要+动名词形式You can get plenty of information on the interent 我觉得那个可能是个拼写错误吧？plenty of 大量的··...
