区别：古时候①although和though同义，在一般情况下，可以互换使用。只是though较普遍，常用于非正式的口语或书面语中，而although则较为正式。另外although语气比though炸厕所重，常用以强调让步概念。
e.g. Though/Although my car is very old, I don't want to buy a new one.
虽然我的汽车很旧，但我不想买一辆新的。
He insisted on doing it although I warned him not to.
虽然我警告他不要做，但他仍然坚持要做。
②even能和though组合表示强调，但even不能和although组合。因此，不能说even although,在这里even though=even if(no matter if; though即使……也……)
e.g. Even if/Even though we could afford it, we wouldn't go abroad for our vocation.
即使我们付得起这笔钱，也不出国度假。
③当让步状语从句指某种假设情况时，通常用though,而不用although。
e.g. Though all the world were against me, I should still hold to my opinion.
就算全世界都反对我，我还是坚持我的立场。
Though everybody derts you, I will not.
电力技术即使所有人都抛弃你，我也不会的。
④though可以独立用作副词，常放在句末，意为all the same (还是；仍然)或however(可是；然而)，而although无此用法。 带有鸟的四字词语
e.g. She didn't tell me what she had done, but I know it though.
死亡英文她没有告诉我她所做的事情，但我还是知道了。
It's hard work. I enjoy it, though.
工作很苦，可是我喜欢。
⑤though引导让步状语从句时可以倒装，而although从句则不能。
e.g. Bravely though they fought, they had no chance of winning.
虽然他们打得很勇敢，但还是没有机会获胜。
相同点：①在although和though引导的让步状语从句中，主句里不可用潜移默化造句but,若要强调前后两部分的对比意义，可在主句前加yet或still。
e.g. Although/Though he has a lot of money, yet/still he is unhappy.
他虽然有很多钱，但并不幸福。
②although和though引导让步状语从句时，常采用省略形式。
e.g. Although tired (=Although he was tired), he kept on working.
虽然很疲劳，但他继续工作。
The problem, though complicated(=though it is complicated), can be solved without much difficulty.
这个问题虽然复杂，但解决起来不会有很大困难。
Even if emphasize a unrealistic situation and partly equals to "on the condition that".
红岩精彩片段摘抄Even though means although, however. It signals a contrary.
even if 即使
even though 即使
despite 为介词 意指 in spite of: 不管
后面接名词结构
even if (=even though)
澳洲留学签证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 derts you, I will not.
