1) I am a student.
2) Mary has a cat.
這類的句型，稱為主動式（Active Voice）。然而，在做動作的主詞不重要、受詞較重要的情況下，我們可用受詞當主詞，稱為被動式（Passive Voice），如：我的車子被偷了 My car was stolen. 誰偷了車，不確定，但車子被偷是確定且重要的。被動式句型：
主詞 + be 動詞 + 過去分詞(p.p) (+by 受詞，因做動作的人不重要，可省略)
其中，原意中必須要有受詞，才能有被動式的形式，因此上面的例句 1) I am a student. 並無受詞，所以無法產生被動式，而 2) Mary has a cat. 主詞為 Mary，受詞為 cat，便可改成被動式 A cat is had by Mary.
主動式：I have a cat. <--- 主詞為 I, 受詞為 cat
被動式：A cat is had by me. <--- 主詞變成 cat，受詞為原先的 I
現在式：He eats an apple. ---> An apple is eaten by him.
過去式：He ate an apple. ---> An apple was eaten by him.
未來式：He will eat an apple. ---> An apple will be eaten by him.
現在進行式：He is eating an apple. ---> An apple is being eaten by him.
過去進行式：He was eating an apple. ---> An apple was being eaten by him.
現在完成式：He has eaten an apple. ---> An apple has been eaten by him.
【練習一】Please transform the sentences into Passive Voice.
1. I sold the car last week.
2. My sister sent a gift to me last month.
3. Cathy wrote five novels.
4. I love my cat.
5. Peggy has received my letter.
6. I will finish the project by tomorrow.
7. He was taking a shower when I called him.
8. She has to call her mother tonight.
1. This picture was took by Lucy.
2. Were the music enjoyed by the audience?
3. These dishes washed by his son.
4. When will the announcement publish?
5. Has Narnia seen by you?
1. The car was sold by me last week.
2. A gift was sent to me by my sister last month.
3. Five novels were written by Cathy.
4. My cat is loved by me.
5. My letter has been received by Peggy.
6. The project will be finished by me by tomorrow.
7. A shower was being taken by him when he was called by me.
8. Her mother has to be called by her tonight.
1. took --> taken
2. Were --> Was
3. washed --> were washed
4. publish --> be published
5. Has Narnia seen --> Has Narnia been seen