although

although (虽然),even though(即使),
though, although在句首表“尽管”两者都可以用。
even if (=even though)
though, although, even if (though)均可引导让步状语从句，但在侧重假设或推断时要用though或as if(though),例如：
Although it rains heavily, we shall still go out
上句中although应改为even if (though)或though。
再如：Though(Even though) everyone deserts you, I will not.

这四个词（词组）都有“虽然、即使、尽管”的意思。even if和even though带有较强的意味，语气比although和though强。though比although通俗，但不如although正式,都不能和but连用，但可以和yet, still或nevertheless连用。可以放在主句前面也可以放在主句后面。even if，even though所接的句子常用虚拟语气。

even if , although

When we use ‘even if’, it has the effect of making the ideas expressed appear more extreme or surprising. ‘Even if’ is used for emphasizing that although something might happen, the situation will not change:

Even if 强调极端，表示‘无论发生什么，原来的情况，还是老样子。’

I shall continue to work from 6 a.m. till midnight, even if it kills me.

Even if I became a millionaire, I would not stop working.

Although 表示 ‘转折’,although表示的情况已存在。

Although I have not attended college, I believe that I am also qualified.
Although he put in all that he knew, he could not match up with you.

even if含有强烈的假定性，而even though强调从句的事实。例如：
Even if he is poor, she loves him. (=He may be poor, yet she loves him.)

即使他很穷，但她还是爱他。
Even though he is poor, she loves him. (=He is poor, yet she loves him. )

尽管他很穷，但她还是爱她。

although, though, as, even though, even if, despite, (in) despite of, in spite of等，除了后三者是介词（短语）外，其余都是从属连词。

一. 从属连词although, though, as, even though, even if的用法

1.在自然语序的让步状语从句中，although, though, even though的用法相同，均可置于句首或从句首，常与动词连用，只是though比另两者要通俗些。如：

Though/Although/Even though it’s hard work, I enjoy it.尽管这项工作艰难，我却喜欢它。

Although/Though/Even though we all tried our best, we lost the game.(=We lost the game although/though/even though we tried our best.)虽然我们已经尽了最大的力量，但还是输了。

注意：上述的句型都不能用as代替though, although或even though。

2.当让步状语从句的动词用一般现在时表示将来的假说或一般的行为习惯时，通常用even though/even if,一般不用though, although和as，如：

Even if/Even though I have to walk all the way, I’ll go there. 即使我得一路走着去，我也要走到那里。

She won’t leave the TV set even though/even if supper’s on the table. 即使晚饭已摆在桌上，她也不愿意离开电视机。

但是，有时though+情态动词+行为动词也可替代even though/even if+动词的一般现在时来表示习惯性的行为。如：

Even if/Even though you don’t like wine（=though you may not like wine）,try a glass of this. 尽管你不喜欢酒，也要喝一杯这样的酒。

3. 当让步状语从句的动词用虚拟式表示与事实相反的假说时，大多数用even though/even if, 而不用though, although和as,如：

It was a sword-thrust, received from twenty to twenty-four hours before, but nothing could have saved him even if/even though he had been tended without delay. 那是一处二十至二十四小时前被剑刺的伤口，但是，即使他当时得到及时的救护，也没法挽救他的命。

You are not stupid. Even though/Even if you were slow at study, you shouldn’t give up your studies. 你并不傻，即使你学得慢一点，也不应该放弃学习。

4.在倒装语序的让步状语从句中，通常用though或as，不用although, even though。如：

Poor though/as I am, I can afford beer. 虽然我穷，我还可以买得起啤酒。

Young as/though I am, I already know what career I want to follow. 尽管我还小，但对要从事的职业已经胸有成竹。

Strange though it may seem, it is true. 尽管这事似乎很奇怪，可是是真的。

Try as he would/might, he couldn’t open the door.虽然他试了几次，却仍打不开那门。

5.在省略了主语、be动词或行为动词的让步状语从句中，常常用though/although,而不用as, even though, even if，如：

Her appointment was a significant（success）,although/though( it was a )temporary success. 她受聘虽然是临时性的，但却是一大成功。

He performed the task well, although/though（he performed it）slowly.尽管他做得有些慢，但把任务完成得很好。

It is a sunny day, though/although (it is) cold. 今天虽然冷，但阳光充足。

注意：上述三句中的although/though可用albeit代替，只是albeit比另两者更文雅、更正式一些，如：

Her appointment was a significant, albeit temporary success.

He performed the task well, albeit slowly.

It is a sunny day, albeit cold.

6.though作副词时表示“尽管如此”，一般置于句末，可用however代替，此时不能用although/even though/as等代替。如：

We all tried our best. We lost the game, though/however. 我们都已尽了最大的力量，尽管如此，我们还是输了。

The task was very hard. He decided to perform it, though/however. 任务很艰巨，尽管如此，他还是决定去执行。

注意：当however置于第二句（表示结果）的句首时，不能用though来代替，如上述两句可改为：

We all tried our best. However, we lost the game.

The task was very hard. However, he decided to perform it.

7.当状语从句用although/though/as/even though时，不能与but连用，但可与yet连用，如：

Although/Though/Even though he is old, (yet) he is quite strong. 虽然他老了，但是还是十分强壮。

Child as/though he is, (yet) he knows a lot of Chinese characters.尽管他是个小孩，却懂得很多汉字。

二、介词（短语）despite/(in)despite of/in spite of的用法

在英语中，despite/(in)despite of/in spite of是介词（短语），都可接名词（短语）、动名词（短语），只是(in)despite of是较古老的用语，这短语中的in可以省略。如：

They had a wonderful holiday, despite/in spite of/(in) despite of bad weather. 尽管天气不好，他们的假日还是过得极为愉快。

Despite/In spite of/(In) despite of wanting to see him again, she refused to reply to his letters.她尽管很想再见到他，但却不愿意给他回信。

Despite/In spite of/(In) despite of the fact that we tried our best, we didn’t win. 尽管我们尽了最大的努力，我们还是没有得胜。

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