Thursday, 11 August 2011

If you went on a diet....


今天有學生問我,以下兩句有什麼分別:

1) If you go on a diet, you will lose weight. 

2) If you went on a diet, you would lose weight. 

兩句的意思都是說: 如果你節食,你會減肥 

但分別在於第二句 (If you went on a diet) 有一個暗示: 我不相信你真的會去節食。第一句並沒有這個暗示。

譬如說,如果你有一個朋友超級肥胖,但他老是說自己沒有問題,還可以多吃點。你心裡知道他一定不會戒口,但你還是為他著想,希望他去減肥。那你就可以說: 

I don't think you'll go on a diet.  However, if you went on a diet, you'd lose weight. 


這就是 past subjunctive 的一個用法。它可以表達出一件事的不真實性 (unreality),或者不可能性 (improbability)。千萬別因為看見 went 這個過去式動詞 (simple past),就以為節食 (went on a diet) 在過去發生。

但如果你的肥胖朋友下了決心要減肥,問你節食有效嗎,那你大概會說: 

If you go on a diet, you'll lose weight. 

讓我們看看更多例子:

(在一個平安的社區) If I came across two men fighting with each other, I would call the police. (暗示 improbability:But I don't expect that I'll come across two men fighting with each other.)

(在一個品流複雜的社區) If I come across two men fighting with each other, I will call the police. (暗示 probability:It's quite probable that I'll come across two men fighting with each other.)

0 comments:

Post a Comment