被動語態(tài)用法：

1)當我們不知道動作的執(zhí)行者是誰，或者沒有必要指出動作的執(zhí)行者時，需用被動語態(tài)。

2)當我們需要強調(diào)動作的承受者時，常用被動語態(tài)。

3)如果需要說出動作的執(zhí)行者， 用by引導出動作的執(zhí)行者。

主動語態(tài)變?yōu)楸粍诱Z態(tài)時，其謂語動詞的時態(tài)要與原句時態(tài)保持一致，其謂語動詞的數(shù)要與新主語保持一致。

主動語態(tài)變?yōu)楸粍诱Z態(tài)時有以下幾種情況：

1)主語+謂語動詞+賓語

將主動語態(tài)的賓語變?yōu)楸粍诱Z態(tài)的主語。

(主動)We bought a book yesterday.

(被動)The book was bought yesterday.

2)主語+謂語動詞+間接賓語+直接賓語

將主動語態(tài)中一個賓語變?yōu)楸粍诱Z態(tài)的主語。多數(shù)情況下將間接賓語變?yōu)橹髡Z。如果直接賓語變?yōu)橹髡Z時，間接賓語前要加介詞to / for.

(主動)He showed me a book yesterday.

(被動)I was showed a book yesterday.

(被動)The book was showed to me yesterday.

3)主語+謂語動詞+復合賓語

含有一個由賓語加賓語補足語構成的復合賓語，變?yōu)楸粍诱Z態(tài)時，將主動語態(tài)的賓語變?yōu)楸粍诱Z態(tài)的主語，賓語補足語保留不變，成為主語補足語。

(主動)I found him a good pupil. (賓語補足語)

(被動)He was found a good pupil. (主語補足語)

4)短語動詞變?yōu)楸粍诱Z態(tài)

有些短語動詞相當于一個及物動詞，其后可以接賓語，因此它們也有被動語態(tài)，但短語動詞是不可分割的整體，變?yōu)楸粍诱Z態(tài)時不可去掉其后面的介詞或副詞。

(主動)We should look after the patients very well.

(被動)The patients should be looked after very well by us.

5)賓語從句變?yōu)楸粍诱Z態(tài)

若主動語態(tài)中是賓語從句，變?yōu)楸粍诱Z態(tài)時常用it作形式主語，而把真正的主語放在后面。

It‘s said that he passed the exam.

被動語態(tài)應注意的幾個特殊問題：

(1)不及物動詞帶介詞和介詞賓語，在變?yōu)楸粍诱Z態(tài)時，仍然要帶上介詞。

(主動)The students in class listen to the teacher carefully.

(被動)The teacher is listened to carefully by the students in class.

(2)當動詞帶有復合賓語時，并且賓補是省去“to”的動詞不定式時，在被動語態(tài)中應加上“to”。

(主動)They make do all the work.

(被動)We were made to do all the work.

(主動)We often hear her sing English songs.

(被動)She is often heard to sing English songs.

(主動)I see him walk to school.

(被動)He is seen to walk to school.

本文來自：逍遙右腦記憶 http://portlandfoamroofing.com/chuzhong/1332672.html

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