1. 表示“虽然”时，不要根据汉语习惯，在后面使用连词but,不过有时它可与 yet, still, nevertheless,等副词连用。

如：他虽然年纪很大了，但还很强壮。

正: Although he is very old,(yet)he is quite strong.

误: Although he is very old, but he is quite strong.

但是在一定的上下文中，类似下面的 although与but连用的句子是可能的往意bt引出的句子在 although从句之前).

如: But ldidn't know that then, although I learned it later.

但我当时的确不知道此事，尽管后来还是知道了。

2. 有时用于主句之后，起补充说明的作用，相当于 however, but。

如: He is poor, although he is well contented.他很穷，然而却能知足常乐

The price increase will obviously be unpopular, although it's unlikely to reduce demand.

价格升高显然会不受人欢迎，然而这不大可能会降低人们的需求。

3. 若主从句主语相同，且从句谓语含有动词be,可将从句主语和动词be省路。

如: Although (he is) quite young, he knows a lot.虽然很年轻，但他很懂事了。

In any case, she was very lovable although not at all tidy.不管怎么讲，她还是很可爱的，尽管一点也不爱干净。

4.不能用于 as though(好像), even though(即使)等习语中代替though,也不用于让步状语的倒装形式中。