進階 · Unit 10
to 不定詞 — 語態
不定詞也是動詞，所以也能區分主動和被動，形態基本上有 to + 原形動詞(主動)、to be + 過去分詞(被動)、to have been + 過去分詞(完成式被動)三種。句子的主詞和不定詞所表示的行為之間，關係是「做的一方」就用主動，是「被做的一方」就用被動。
概念說明
不定詞也是動詞，所以也能區分主動和被動，形態基本上有 to + 原形動詞(主動)、to be + 過去分詞(被動)、to have been + 過去分詞(完成式被動)三種。句子的主詞和不定詞所表示的行為之間，關係是「做的一方」就用主動，是「被做的一方」就用被動。
A. 主動 — to + 原形動詞
句子的主詞是不定詞這個行為的「做的一方」時，就用主動形態 to + 原形動詞。這是到目前為止學過的最基本形態，主詞和不定詞之間會自然成立「做」的關係。
| 例句 | 關係 | 形態 |
|---|---|---|
| I want to help you. | 我幫忙 | to V |
| She hopes to win the prize. | 她獲勝 | to V |
| He plans to visit us. | 他拜訪 | to V |
- I decided to leave early. (我決定早點離開。)
- She wants to learn Japanese. (她想學日文。)
- They agreed to sign the contract. (他們同意在合約上簽名。)
B. 被動 — to be + 過去分詞
句子的主詞是不定詞這個行為的「被做的一方」時，就用被動形態 to be + 過去分詞。請記住 to be + 過去分詞 = 被動 這個公式。主要常用在「必須被~、希望被~、預定會被~」的語境裡。
| 例句 | 關係 | 形態 |
|---|---|---|
| The report needs to be finished. | 報告被完成 | to be p.p. |
| The car has to be fixed. | 車子被修理 | to be p.p. |
| She hopes to be invited. | 她被邀請 | to be p.p. |
- These emails need to be answered today. (這些電子郵件今天必須回覆。)
- The room has to be cleaned before the guests arrive. (客人來之前房間必須打掃乾淨。)
- He hopes to be promoted next year. (他希望明年能升職。)
- The children want to be picked up at three. (孩子們希望三點有人來接他們。)
C. 完成式被動 — to have been + 過去分詞
要表示發生在更早時間點的被動情況時，就用完成式被動 to have been + 過去分詞。這是把完成式不定詞和被動結合起來的形態，傳達「比主要子句更早之前被~了」的意思。請用下面的表格記住這四種形態。
| 語態、時態 | 形態 | 例子 |
|---|---|---|
| 主動、同一時間點 | to + V | seems to solve |
| 被動、同一時間點 | to be + p.p. | seems to be solved |
| 主動、更早的時間點 | to have + p.p. | seems to have solved |
| 被動、更早的時間點 | to have been + p.p. | seems to have been solved |
- The letter seems to have been written in a hurry. (那封信好像是匆忙寫成的。)
- The door appears to have been left open. (那扇門好像一直開著沒關。)
- The old bridge is said to have been built 200 years ago. (據說那座古橋是 200 年前建造的。)
- She is proud to have been chosen as the leader. (她很自豪自己曾被選為領導者。)
重點整理
- 1句子的主詞是不定詞行為的「做的一方」就用 to + 原形動詞，是「被做的一方」就用 to be + 過去分詞，每次都要先做這個判斷。(例: She wants to invite / She wants to be invited.)
- 2更早時間點的被動要用 to have been + 過去分詞來表示，這是把完成式不定詞和被動合在一起的形態，請記住這條結合規則。(例: The letter seems to have been written.)
- 3need、want、hope、have to 後面常常接被動不定詞，用來表示「必須被~、希望被~」的意思，請記住這個實戰句型。(例: This needs to be done.)
- 4中文的「必須被~、想被~、好像被~了」大多對應到被動的不定詞，請培養這種語感。(例: needs to be sent, seems to have been broken.)
- 5把不定詞的語態和時間點組合起來，就會出現 to V / to be p.p. / to have p.p. / to have been p.p. 這四種，用表格記住這個全貌，實戰時就能立刻選出要用哪一個。
例句
I want to send this package today.
我想今天寄出這個包裹。
She hopes to meet the author someday.
她希望有一天能見到那位作家。
They agreed to help with the moving.
他們同意幫忙搬家。
This letter needs to be sent by Friday.
這封信必須在星期五之前寄出。
The car has to be repaired this week.
這台車這個星期必須修好。
這個單元還有更多例句。註冊後可以看完整內容並聆聽發音。
容易犯的錯誤
This letter needs to be sent today.
She hopes to be invited to the party.
The window seems to have been broken.
The car has to be fixed this week.
The house is said to have been built in 1920.