You use although to introduce a subordinate clause which contains a statement that contrasts with the statement in the main clause.
even though
Although he is known to only a few, his reputation among them is very great.
尽管只有少数人知道他,但是他在这些人中的名声却很大。
You use although to introduce a subordinate clause which contains a statement that makes the main clause of the sentence seem surprising or unexpected.
though , even though
Although I was only six, I can remember seeing it on TV.
虽然当时我只有6岁,我还能记得在电视上看见过它。
You use although when admitting a fact about something that you regard as less important than a contrasting fact.
even though
Although they're expensive, they last forever and never go out of style.
尽管价格昂贵,但它们经久耐用并且永不过时。