1 though, although:虽然though, although 当“虽然”讲，但是它们不能和 but 连用。
Although he was tired, he went on working.
=He was tired but he went on working.
=He went on working though he was tired.
(×)Although he was tired but he went on working.
I was late for the last train although(though)I hurried.
Though he is young, he knows a lot.
=Young as he is, he knows a lot.
2 even if =even though “即使…………，也”Even if (Even though)your teacher said so, you need n ot believe him.
Even though(Even if) it is raining, we’ll go.
Even if I were busy, I would go.（虚拟语气）
Even if I am busy, I will go.（陈述语气）
even if 和even though 所引导的状语从句中的动词用陈述语气或
3 复合关系词引导的状语从句You may go wherever you like.
=You may go to any place where you like. （定语从句）
Whenever he comes, he asks the same question.
=At any time when he comes he asks the same question.
=No matter when he comes, he asks the same question.
I will buy the book, however expensive it is.
=I will buy the book ,no matter how expensive it is.