主动语态变成被动语态的步骤是：

1.将宾语变成主语

2.把谓语变成被动结构，时态要跟原主动语态时态相符

3.原主语如果有必要留下，则用介词by引导放在动词之后，将主格改为宾格。

例句如下：

①He mended the bike yesterday.

他昨天把车修好了。

→The bike was mended by him yesterday.

②We study English in our school.

我们在学校学习英语。

→English is studied (by us) in our school.

③We can't put our bikes here.

我们不能把车停在这里。

→Our bikes can't be put here.

④The Young Pioneers are planting trees by the river.

少先队员们正在河边植树。

→Trees are being planted by the Young Pioneers by the river.

1.把主动语态的宾语变为被动语态的主语。

2.把谓语变成被动结构(be＋过去分词)，根据被动语态句子里的主语的人称和数，以及原来主 动语态句子中动词的时态来决定be的形式。

3.把主动语态中的主语放在介词by之后作宾语，将主格改为宾格。例如：

1) All the people laughed at him.= He was laughed at by all people.

2) They make the bikes in the factory.= The bikes are made by themin the factory.

记忆歌诀：宾变主，主变宾，by短语后面跟。谓语动词变被动，be后“过分”来使用