先做一下下面两道试题，如果感觉吃力，请你认真学习本文，如果你感觉简单，答案又正确的话，请直接跳过，不过可能还会吃亏，因为我今天的知识点非常重要，我的讲义里例句都是经典的，许多地方都是意想不到的考点。最好还是认认真真地看看本文吧，嘿嘿。

1、Mary ____ my letter ;otherwise she would have replied before now.

A has received B ought to have received

C couldn't have received

D shouldn't have received

2、where have you been?

I______in the heavy traffic,otherwise I_______here earlier.

A got stuck; would have come

B got stuck ;was

C have got stuck ;would have come

D had got stuck; would come

1、otherwise可表示含蓄虚拟的条件，主句用陈述语气（该声明时态用声明时态），从句用虚拟语气用would have done形式表达.

如：We didn’t know you were in trouble at that time, otherwise we would have given you a hand.

我们当时不知道你遇到了困难,要不然我们会帮助你的.

除了otherwise（否则，要不然）以外,能够表示这种虚拟条件的词和短语还包括：but that（要不是）、without（没有）or（不然）、under．．．circumstances（在……的情况下）、in the past（在过去）等等.

Luckily he reminded me. Otherwise I'd have forgotten all about it.

亏他提醒了我，要不我早忘了。

He reminded me of what I should otherwise have forgotten.

他提醒了我, 要不然（如果没有提醒我）我就会把这件事给忘了。

His advice has made the design better than it would otherwise have been.

他的建议使得这个设计要比它本该是(如果未采纳他的建议)的样子要好。

My parents lent me the money. Otherwise, I couldn't have afforded the trip.

我父母借钱给我了。否则，我可付不起这次旅费。

We're committed to the project. We wouldn't be here otherwise.

我们是全心全意投入这项工作的，否则我们就不会到这里来了。

2、注意：otherwise与or的区别

otherwise用于表示否定条件，指如果不做某事，就会发生不好的事，含告诫、威胁之意，语气强于 or。

Shut the window, otherwise it'll get too cold in here.

把窗户关好，不然屋子里就太冷了。

Don't move, otherwise I'll kill you [ you'll be shot dead].

不许动，要不我就崩了你。

Be modest, otherwise you will lag behind.

要谦虚，否则就要落后。

Do it now, otherwise you'll be fired.

现在就做，否则就解雇你。

Hands up, otherwise you will be shot.

举起手来，否则就毙了你。

Put your coat on, otherwise you'll catch a cold.

穿上外套，不然你会感冒的。

or词义同 otherwise，但语气较弱，多用于口语，也可与 else 合用。

〔例证〕

Get away, or (else) I'll call the cops.

滚开，不然我就打电话叫警察了。

Hurry up or (else) we'll be late.

抓紧时间，不然的话我们就要迟到了。

答案：1、C ；2、A