1.两词同义并可换用，但a|though语气较重，通常放在句首并用于正式场合。例如: I'd quite like to go out, (al)though it is a bit late.

我很想外出，虽然为时稍晚。

though it was snowing, it was not very cold

虽然下着雪，但并不很冷。

2用 though时，可将强调的词前置，但 although不能。as也有此种倒装结构。

例如：Poor though/as he is, he is happy.虽然他穷，但过得很愉快。

Child though /as she was, the actress was drawing a crowd.

尽管还是个孩子，这个女演员却引起了人们的注目。

(child前无冠词a)

3 although引导的从句常指事实;,而 though引导的句子可表假设。

例如: Let's start as arranged though it rains tomorrow.即使明天下雨，咱们也按预定的计划出发吧。(假设)

He was not unhappy although he had to live alone.

虽然得一个人生活，他毫无不快之感。(事实)

4. although只用作连词，而 though除作连词外，还可用作副词，常置句末，句子较长时，也置于句中。

例如: It's hard work, I enjoy it though.

这是苦差事，可我干得颇有乐趣。

There's no excuse, though, for hurting her feelings.

伤到她的感情一事，还是不可原谅。

5. though可用于 even though, as though等结构,although则不能。

例如: Even though I fail, I'll keep on trying.我纵然失败，仍会继续尝试下去。

You look as though (as if) you know each other.看起来你们好像彼此认识。

6. although和 though用作连词时不能和bu连用，但可跟yet,still等连用。

例如: Although he lives alone, yet he is happy.- He lives alone, but he is happy.他虽然单独生活，但很愉快。

7. though常用于省略句。

例如: Though(he is) alone, he is happy.

虽然他独自一人，他非常快乐。