1、条件状语从句由连词if, when(如果),unless, as long as, in case, so far as, provi颊俄岿髭ding that, supposing/supposed that, on condition that等引导
2、条件状语从句要注意时态的正确使用,当主句是将来时的时候,从句要用一般现在时,而主句用情态动词作为谓语时,从句要用一般现在时,主句为祈使句时,从句要用一般现在时
3、方式状语从句由连词as, as if, as though, just as... so ..., the way等来引导, as, just as...so引导的方式状语从句通常位于主句后,当just as ...so结构位于句首时,as从句带有比喻的含义
4、as if 和as though的意义和用法相同,引出的状语从句谓语多用虚拟语气,表示与事实相反,有时也用陈述语气,表示所说的情况是事实或实现的可能性较大
5、让步状语从句由连词although, though, as, even if, while, when, whether...or not, 疑问词+ever, no matter+疑问词等引导
6、as/though表示虽然,尽管,引导的让步状语从句一般用倒装,要将表语或状语提前(名词,形容词,副词,分词,实义动词提前)例如,Hard as she works, she makes little progress