1．以after和before引导的状语从句的主语若与主句主语一致时，可用after和before与从句谓语动词的动名词(短语)形式构成介词短语作状语。 例如：

　　After she sang，she left the rich man's house．(简化前)

　　After singing，she left the richman's house．(简化后)

　　2．以as soon as引导的状语从句的主语若与主句主语一致时，可用on十v-ing形式简化状语从句，此时的动词为非延续性动词。例如：

　　Dr．Bethune began to operateon the wounded soldiers as soon as he arived at the village．(简化前)

　　Dr．Bethune began to operateon the wounded soldiers on arriving at the village．(简化后)

　　3．时间状语从句和条件状语从句的主语和主句主语一致时，有时可简化为不定式作状语。例如：

　　She stopped when she saw her husband．(简化前)

　　She stopped to see her husband．(简化后)

　　If you want to understand the farmers，you must go to the countryside．(简化前)

　　To understand the farmers，you must go to the country side．(简化后)

　　4．结果状语从句和目的状语从句的主语与主句主语一致时，可以简化为不定式作状语；若两者主语不一致时，则应简化为不定式的复合结构作状语。例如：

　　He was so tied that he couldn't go any further．(简化前)

　　He was too tied to go any further．(简化后)

　　I came here so that I could ask some questions．(简化前)

　　I came here(in order) to ask some questions．(简化后)