一、分词在句子中作状语，可以表示时间、条件、原因、结果、让步、伴随等。
分词（短语）作状语时，其逻辑主语应与句中主语相一致。当现在分词表示的动作发生在谓语动词之前时, 则用现在分词的完成式；当所表示的动作与谓语的动作同时发生, 则用现在分词的一般式。完成或被动关系用过去分词。

二、现在分词作状语时，其逻辑主语应该与句子的主语一致，但有时现在分词的主语与其所在句中的主语并不一致，这种现在分词即所谓的垂悬现在分词。垂悬现在分词容易使句意模糊，甚至造成歧义，因而通常被认为是不合规范或错误的用法。
1.Searching along the deck，it had taken him some time to find a doctor.
他沿着甲板找了好久才找到一名医生。(searching的逻辑主语是句中的him)
2.Walking or sleeping，this subject was always in my mind.
不论是走路或睡觉，我总是在想着这个问题。(walking or sleeping的逻辑主语是句中的my)
3.Traveling is interesting but tiring.
旅行是有趣的，但是使人疲劳
4.The pupils will get confused if they are made to learn too much.
如果让学生学得太多，他们会感到糊涂的。
5.The argument is very convincing.
他的论点很令人信服。
6.They were very excited at the news.
听到这个消息，他们非常激动。

三、现在分词或过去分词作状语时，有时可以在分词前加while，when, once, although, until, if等连词。
1.When leaving the airport, she waved again and again to us.
2.While waiting for the train, I had a long talk with my sister about her work……
3.Once recovered, he threw himself into his work and made every effort to do it well.
4.Although working very hard, he failed to pass the final exam.
5.If translated word by word, the passage will be difficult to understand.