分词逻辑主语的不一致性与独立主格结构
在通常情况下，分词作状语时它的逻辑主语应与句子主语一致，若不一致，则应改用其他句型，如：
误：Crossing the road, a car knocked him down.
正：Crossing the road, he was knocked down by a car. 过马路时他被车撞倒了。
正：When he was crossing the road, a car knocked him down. 他过马路时车子把他撞倒了。
解决状语分词的逻辑主语与句子主语不一致的问题，也可在分词前加一个名词或代词，使之成为分词的逻辑主语。由于加在分词前的名词或代词要用主格形式，故称分词的独立主格结构。如：
The test finished, we began our holiday. 考试结束了，我们开始放假。
Weather permitting, we are going to visit you tomorrow. 天气允许，我们明天去看你。
The weather being fine, we went swimming. 天气很好，我们就去游泳了。
He being absent, nothing couldn’t be done. 由于他缺席，什么事也干不成。