语态有两种：主动语态和被动语态。主语是动作的发出者时为主动语态；主语是动作的接受者时为被动语态。 注意：1）感官动词主动语态的宾语补足语是不带to 的不定式，变为被动语态时，该不定式前要加\"to\"。例如： the teacher made me go out of the classroom. 老师逼我走出教室。 --> i was made to go out of the classroom （by the teacher）. we saw him play football on the playground. 我们看见他在草场踢球。 --> he was seen to play football on the playground. 2）情态动词+ be +过去分词，构成被动语态。例如： coal can be used to produce electricity for agriculture and industry. 煤可以产生工农业需要的电。
