=Confused by the new surrounding, I was hit by the lack of fresh air.

3. As I was exhausted, I slid into bed and fell fast asleep.

　Exhausted, I slid into bed and fell fast asleep.

Compare

1. Following the old man, we went upstairs.-we followed (跟着那个老人, 我们上去了)

2. Followed by the old man, we went upstairs. (we were) (被那个老人跟着, 我们上去了)

3. 从上面看,体育场好像一个鸟巢。

____ from the top, the stadium looks like a bird nest.

A. Seeing B. Seen

4. 从太空看, 宇航员看不到长城。

____ from the space, the astronaut can not discover the Great Wall.

A. Seeing B. Seen

Difference between the Present Participle and the Past Participle

Used for a long time, the book looks old. 由于用了很长时间，这本书看上去很旧.

Using the book, I find it useful. 在使用的过程中，我发现这本书很有用.

Looking at her, he jumped with joy. Looked at by her, he jumped with joy.

注意：选择现在分词还是过去分词，关键看主句的主语。如分词的动作是主句的主语发出，分词就选用现在分词，反之就用过去分词。

> 现在分词与过去分词作状语的区别

1. 逻辑关系

现在分词作状语与过去分词作状语的最主要区别在于：两者与所修饰的主句的主语的逻辑关系的区别。

1） 现在分词作状语时，现在分词所表示的动作与句子主语之间构成逻辑上的主动关系。

He went out, shutting the door behind him. 他出去后将门随手关上。

Not knowing what to do, he went to his parents for help. 由于不知如何办是好，他去找父母帮忙。

2） 过去分词作状语时，过去分词所表示的动作与句子主语之间构成逻辑上的被动关系。

Given more encouragement, the boy could have behaved better.

如果多给这个孩子一些鼓励，他本来会表现得更好。

Faced with difficulties, we must try to overcome them. 在遇到困难时，我们必须设法克服。

3） 部分过去分词来源于系表结构，作状语时不表示"被动关系"，其前不用being。这样的

过去分词及短语常见的有：lost in（陷入某种状态）、seated（坐着的）、hidden（躲着）、stationed（驻扎）、lost/absorbed（沉溺于）、 born in（出身于）、dressed in（穿着）、tired of（厌烦了）等。

Lost/Absorbed in deep thought, he didn't hear the sound. 因为沉溺于思考中，所以他没有听到那个声音。

Born in this beautiful town, he hates to leave it. 出生于这个美丽的小镇，他不愿离开它。

1. 时间概念

过去分词所表示的动作发生在谓语动作之前，或表示"一种状态"，与谓语动作同时发生或存在。