什麼是虛主詞 it？ 2 個觀念讓你立刻學會虛主詞

如果一個句子的主詞太長（是的，主詞可以是句子而不只是單字），往往我們用 it 代替原本的主詞讓句子不要頭重腳輕。

• To work 10 hours a day is very tiring.

  一天工作 10 小時很累人。
• That you finish the work on time is important.

  你準時完成工作很重要。

用虛主詞的兩種情況（不定詞片語、that 子句）

第一句的主詞是不定詞片語 to work 10 hours a day。但像我面講的，to work 10 hours a day 講起來很繞口。所以，用虛主詞 it 代替原本的不定詞片語。

• It is very tiring to work 10 hours a day.

第二句的主詞是 that 子句 that you finish the work on time，但通常 that 子句不會放在句子的最前面，所以一樣用虛主詞 it 代替。

• It is important that you finish the work on time.

除了代替不定詞片語和 that 子句，需主詞 it 還需要填補某些缺少主詞的情況。

英文句子一定需要一個主詞，所以如果一個句子沒有明確的對象像是在講天氣、時間、日期，那就要給這句子一個虛主詞 it。

用虛主詞 it 的其他情況

形容時間

• It is two o’clock.
• It is Wednesday
• It’s the 24th.

形容天氣

• It is cloudy.
• It is raining.
• It is going to rain.

形容所花的時間

• It takes me two hours to drive to Taipei.
• It takes 12 hours to fly to new York from Taipei
• It takes me 30 minutes to do the dishes.

其實，以上這三句都是開頭講的 it 代替不定詞片語。你應該有注意到這三個 to 開頭的不定詞片語

• to drive to Taipei
• to fly to new York from Taipei
• to do the dishes（do the dishes = 洗碗）

但我發現大家很容易忘記這三個句子，所以我才在這裡重新強調一次，順便提醒你要把這三句背好。

虛主詞 it 小測驗

把以下 5 個頭重腳輕，主詞太長的句子用虛主詞 it 代替，解答在下面。 

1. That you finished your homework is good.
2. To go to school is important.
3. To finish the work on time is impossible.
4. To be stuck on the train was horrible.
5. That he was so late was terrible.

解答

1. It is good that you finished your homework.
2. It’s important to go to school.
3. It’s impossible to finish the work on time.
4. It was horrible to be stuck on the train.
5. It was terrible that he was so late.