现在分词作状语的用法及与过去分词作状语的区别
1现在分词的一般式doing,
现在分词的一般式所表示的动作与句中谓语动词同时发生。
Seeing the cat, the mouse ran off.一看到猫，老鼠就跑了。
2 现在分词的完成式 having done
现在分词的完成式所表示的动作先于句中谓语动词发生。
The storm left, having caused a lot of damage to this area.暴风雨离开了，给这个地区造成诸多破坏。
3 现在分词的被动式 being done
现在分词的被动式表示与谓语动作同时发生的被动动作。
Being protected by many guards, he felt safe.由于有很多警卫保护，他觉得很安全。
4 现在分词的完成被动式 having been done
现在分词的完成被动式表示发生在谓语动作之前的被动动作。
Not having been invited, he felt very unhappy. 由于没有被邀请，他感到很不高兴。
5 现在分词的否定式在其前面加not
Not having completed the programme, they have to stay there for another two weeks. 由于没有完成计划，他们不得不在那里再呆两个星期。
6现在分词作状语的基本用法
1）表示时间
Walking along the street, I met Mary. (=While I was walking along the street,…) 在街上散步的时候，我遇见了玛丽。
2）表示原因
Being tired, I stopped to take a rest. (=Because I was tired,…)
因为疲劳，我停下来休息。
3）表示条件
Turning to the left, you will find the school. (=If you turn to the left,…)
向左转，你就会找到那所学校。
4）表示让步
Knowing where I live, he never comes to see me. (=Though he knows where I live, …) 虽然他知道我的住址，但他从不来看我。
5)表示伴随/方式
I stood there, waiting for her. (=…，and waited for her.)我站在那儿等她。
6）表示结果:现在分词表示自然而然的结果
Their car was caught in a traffic jam, thus causing a delay.他们的汽车遇上了交通堵塞， 因而耽搁了。thus 副词，修饰causing。
7 现在分词作状语表示分词动作的执行者（逻辑主语）就是句子的主语，有时候这类结构可以看作状语从句的省略。
When crossing the street,do be careful.过马路时，务必要小心。
As long as going into the reading room, you should keep quiet.只要进入阅览室，你就应该保持安静。
Though lacking money, his parents managed to send him to the university. 尽管缺少钱，他的父母还是设法送他上了大学。
8 当现在分词的逻辑主语不是句子的主语，而是一个名词或代词时，这种带逻辑主语的现在分词是独立主格结构的一种。独立主格结构和分词一样，在句中作状语。有时也可使用从句。
Time permitting,we’ll come to see you.如果时间允许，我们就来看你。
All the tickets having been sold out, they went away disappointedly.
所有的票已经卖光了，他们失望地离开了。
9少数现在分词（短语）没有逻辑主语，其形式的选择不受上下文的影响，称作独立成分。
Generally speaking一般来说 judging from/by由…来判断 seeing…/considering…考虑到 providing that…如果…
supposing即使；如果…… assuming…假使……
Judging from his accent, he is from the south.从他的口音来判断，他是南方人。
Considering your health, you’d better have a rest.考虑到你的健康，你最好休息一下。
10 过去分词作状语，表示该动词与句子的主语之间是被动关系。
Moved by the young man’s heroic deed, I couldn’t hold back my tears.
被这个青年的英勇行为所感动，我禁不住留下了眼泪。
习题
1 Whenever he was asked why he was late, he would answer carelessly, always _____(say) the same thing.
2 The manager, ______ (make) it clear to us that he didn’t agree with us, left the meeting room.
3 He was busy writing a story, only _____(stop) once in a while to eat some food.
4 The old man,_____(work) abroad for twenty years, is on the way back to the motherland.
5 When _____help, one often says “Thank you”or “It’s kind of you.”
A. offering B. to offer C. to be offered D. offered
6 ____ a white uniform, he looks more like a cook than a doctor.
A. Dressed B. To dress C Dressing D. Having dressed
答案 1saying
2 having made经理明确表示他不同意我们的观点后，就离开了会议室。
3 stopping 他忙于写一个故事，只是偶尔停下来吃一些东西。once in a while偶尔
4 having worked 5 D 过去分词表被动
6 A 穿着白色的制服，他看起来更像一个厨师而不是医生。