(1)although與though可以引導讓步狀語從句,不能與but連用,但可以與yet連用.
　　Although they are poor,(yet)they are warm-hearted.
　　(2)even if或even though引導讓步狀語從句,表示"即使","縱然",用來使人注意下文所強調內容的性質.
　　I'll get there even if(though)I have to sell my house to get enough money to go by air.
　　(3)no matter后接上who、what、where、how等疑問詞,也可以在這類疑問詞后面加上ever構成whoever、whatever、wherever、however等.
　　Don't trust him, no matter what / whatever he says.
　　Whoever breaks the law will be published.
　　No matter how hard the work is, you'd better try to do it well.
　　(4)as也可以引導讓步狀語從句.要用倒裝.
　　Child as(though)he is, he knows a lot.
　　Much as I like it, I won't buy.
　　Try as he would, he couldn't lift the heavy box.