过去分词做状语
过去分词作状语的类型有：
过去分词作状语，可以表示时间、让步、条件、原因、方式等，相当于一个状语从句。其逻辑主语为主句的主语，且与主句主语构成逻辑上的动宾关系。
1、作时间状语
相当于时间状语从句。可在过去分词前加上连词when，while，until等，使其时间意义更明确。
Seen from the top of the hill，the town looks more beau-tiful.
=When the town is seen from the top of the hill，it looks more beautiful.
=When seen from the top of the hill，the town looks more beautiful.
从山顶往下看，这座城镇看起来更加漂亮。
When asked for his views about his teaching job，he said he found it very interesting and rewarding.
当问到对教学工作的观点时，他说他觉得既有趣又有意义。
2、作原因状语
相当于原因状语从句。
Satisfied with what I did,my teacher praised me in class.
=Because my teacher was satisfied with what I did，he praised me in class.
由于对我所做的事情感到满意，老师在班上表扬了我。
3、作条件状语
相当于条件状语从句。可加连词if，unless等转换成条件状语从句。
Grown in rich soil，these seeds can grow fast.
=If they are grown in rich soil，these seeds can grow fast.如果种在肥沃的土壤里，这些种子就能长得快。
