1. 含有双宾语的主动语态在变被动语态时，通常将指人的间接宾语变为被动语态的主语；也可将指物的直接宾语作为被动语态度的主语，但应在间接宾语前加上介词to(谓语动词多为pass, give, teach, bring, send, show, write等) 或for (谓语动词多为buy, make, draw, keep等)。如：

His aunt gave him a nice present yesterday.

→He was given a nice present by his aunt yesterday./A nice present was given to him by his aunt yesterday.