表示“虽然”，两者大致同义，可换用，只是 although 比 though 更为正式：
Though [Although] it was raining，we went there. 虽然下着雨，但我们还是去了那儿。
Though [Although] it was barely four o’clock, the lights were already on. 尽管才四点钟，灯已经亮了。
Though [Although] we are poor, we are still happy. 我们虽然穷，仍然很快活。
although 一般不用作副词，而 though 可用作副词，且一般放在句末（不放在句首），意为“可是”、“不过”：
It’s hard work; I enjoy it though. 工作很辛苦，可是我乐意干。
He is looking fit, though. 但他看起来很健康。
You can count on him, though. 不过你可以指靠他。
although的用法1：although的基本意思是“尽管，虽然”或“然而，但是”，常用于引导陈述语气的让步状语从句，且引导的句子常指事实，而不指设想。
although的用法2：although可置于句首（此时多用逗号与主句分开），也可置于句末（此时用不用逗号均可），也可用于句中表强调。
although的用法3：在although引导的复合句中，若主句和从句的主语相同，且从句的谓语动词含动词be，则从句的主语和动词be可以省略。
although的用法4：although不能与but在句中同时出现，即有了although就不可以再用but。但although可与副词yet连用而产生关联关系，在含让步状语从句的主句中还可以使用nevertheless, still等副词。
although的用法5：although not是口语中的习惯说法， although not前后呼应的词须是同类词。例如：With all her faults,I love her and I usually agree with her, too, although not always.尽管她有各种各样的缺点，我仍然爱她，我也通常与她观点一致，虽然不总是这样。
although的用法6：在一定上下文中although也可与but连用，不过此时but须置于although之前，意为“但尽管…”。
在 as though（好像，仿佛），even though（即使，纵然）等固定短语中不能用 although：
She closed her eyes as though she were tired. 她闭上眼，仿佛很疲劳似的。
We felt as though we had witnessed the whole thing. 我们感到仿佛目击了整个这件事似的。
He is an honest man, I must say, even though I have opposed him. 尽管我反对过他，我还得说他是一个诚实的人。
She was always afraid of men, even though she had lots of boyfriends. 尽管她有很多男朋友，她总是害怕男人。
though 引导的让步状语从句可用部分倒装的形式（注意：倒装后位于句首的名词之前不用冠词），但 although 一般不这样用：
Poor though I am, I can afford it. 我虽穷，但这东西还是买得起的。
Child though he was, he did quite well. 他虽是孩子，但干得很好。
though，as
这些连词均可表示“虽然，尽管”之意。
though 和although在意义上几乎毫无区别，但文体上后者是较正式用词，语气比though强。此外，在习惯用法上这两个词仍有以下一些差异：1.though可引出倒装语序的让步状语从句，although 则不能。2.though可与even连用，although则不能；在as though结构中，只用though，不能用although。3.though可以置于从句末，而although则不能。4.引出省略句时，通常用though。
as 引出让步状语从句只用于倒装语序结构中，语气强于上述两个连词。