文档介绍：Grammar
过去分词作状语
过去分词在句中一般能作时间、原因、条件、让步和方式状语。如：
表示原因，相当于由as, since, 或because引导的原因状语从句
Caught in a heavy rain, he was all wet.
因为淋了一场大雨，所以他全身湿透了。
(Because he was caught in a heavy rain)
表示条件,相当于if, unless引导的条件状语从句
如果种在肥沃的土壤里，这些种子能长得很快。
Grown in rich soil, these seeds can grow fast.
(If these seeds are grown in rich soil)
Compared with you, we still have a long way to go.
(If we are compared with you)
表示伴随情况或方式:
The trainer appeared, followed by four little dogs.
训练员出现了，后面跟着四条小狗。
He walked up and down the room, lost in thought.
他在屋子时走来走去，陷入了沉思。
表示时间
When heated,
ice can be changed
into water.
（When ice is heated,）
表示让步，相当于although/though引导的让步状语从句
Left at home, John didn’t feel afraid at all.
(Although he was left at home,)
Even if invited, I will not take part in the party.
(Even if I am invited,)
小结
过去分词在句中作状语，过去分词的逻辑主语要和句子的主语一致。
位置：过去分词作状语，可以放在主句的前面或者后面，用逗号将二者隔开。
连词+过去分词作状语
有些过去分词可以用连词加以强调。这些连词有when, once, if, unless, though, as if, although, even if, even though, than, as
过去分词与现在分词作状语的区别
Following the old man, we went upstairs.
=We followed the old man, and we went upstairs.
Followed by the old man, we went upstairs.
=We were followed by the old man, and we went upstairs.