1、地点状语从句由连词where, wherever等引导，例如Make a mark where you have a question, 在你有疑问的地方做个标记。
2、原因状语从句由连词because, as, since, when（既然）, now that等引导，如the little boy was crying because he was criticized。
3、目的状语从句由so that, in order that, in case等引导，例如my little brotherstudied hard so that he could pass the exam。
4、结果状语从句由so that, so ....that..., such... that....等引导，例如she was ill, so that she didnt attend the meeting， 她生病了，所以她没能参会。
