什么叫过去分词和现在分词？

Answer 1

【过去分词】
规则动词的过去分词一般是由动词加ed构成(具体规则见后)，不规则动词的过去分词见不规则动词表。
过去分词则属于类动词
1. 及物动词的过去分词作表语,与句子主语是被动关系,表示主语的状态,不但表示被动,还表示已完成了.
The cup is broken. 茶杯破了.
2. 不及物动词的过去分词作表语,与句子主语是主动关系,表示主语的状态,只表示动作的完成.
He is retired. 他已退休.
3. 有些过去分词作表语时,构成的谓语很接近被动结构.
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【现在分词】
现在分词（Present Participle）(又称-ing形式、现在进行式) ，是分词的一种，分词又分为现在分词和过去分词，它们都是非限定动词，即在句子里面不能单独充当谓语，但能充当其它的一些成分（定语，表语，补语和状语），并且它们具有动词的性质，所以又是类动词的一种。
1.构成形式
doing （特殊的略） 现在分词表示主动的或进行的动作
2.时态与语态
一般式doing 一般被动式being done 完成式having done 完成被动式having been done
所有否定式都是在－ing前面加not 包括独立主格形式
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【过去分词】和【现在分词】的差别：
现在分词和过去分词主要差别在于：现在分词表示“主动和进行”，过去分词表示“被动和完成”(不及物动词的过去分词不表示被动，只表示完成)。分词可以有自己的状语、宾语或逻辑主语等。
1)分词作状语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。分词做状语时，它的逻辑主语与句子的主语一致。作状语的分词相当于一个状语从句。
【例如】
Hearing the news, they all jumped with joy. Using what you know of word stems and word formations, you can make a guess at the meaning of a new word.
The students went out of the classroom, laughing and talking. Accompanied by his friend, he went to the railway station.Given better attention, the plants could grow better.
He looked tired and depressed, visibly disturbed by the news of his mother's illness.
分词在句子中作状语，使用何种分词，要取决于分词与句子主语的关系：主谓关系用现在分词，动宾或被动关系用过去分词。

【例如】
Notshavingsenough hands, we turned to them for help.(we don't have enough hands).
Taught by mistakes and setbacks, we have become wiser and handled our affairs better. (we are taught/teach us) .Inspired by the International, the working people of all countries have been fighting for their final liberation. (the working people were inspired/ inspire the working people)____the earth to be flat, many feared that Columbus would fall off the edge. (CET-4 1996,6)
A)shavingsbelieved B) Believing C) Believed D) Being believed

本句意思为：相信地球是平的，许多人担心哥伦布会从边上掉下去。许多人与相信之间是主谓关系，及分词与主语之间为主谓关系。因此，应用现在分词，答案为B.

No matter how frequently ____, the works of Beethoven always attract large audiences. (CET-4 1995,6)
A) performing B) performed C) to be performed D) being performed
本句中贝多芬的作品被反复表演，可见分词与句子的主语之间是被动关系，应该用过去分词，故答案为B.

____as it was at such a time, his work attracted much attention. (CET-4 1996,1)
A) Being published B) Published C) Publishing D) To be published
本句中as引导的是让步状语从句，意思为：他的作品尽管在被这样的时候出版，还是引起了关注，可见分词与句子的主语之间是被动关系，应该用过去分词，故答案为B.

Answer 2

一、现在分词
现在分词由动词加ing构成。
非谓语动词中的现在分词主要起形容词和副词的作用，在句中作定语、表语、补语或状语。
一、现在分词的两个基本特点。
1. 在时间上表示动作正在进行。例如： a developing country. 一个发展中的国家， boiling water 沸水， rising sun 冉冉升起的太阳。（试比较： a developed country 一个发达国家， boiled water 白开水， risen sun 升起的太阳）
2. 在语态上表示主动。例如： the ruling class 统治阶级， the exploiting class 剥削阶级。（试比较： the ruled class 被统治阶级， the exploited class 被剥削阶级）
二、掌握现在分词的基本功能。
1. 现在分词作定语，表示正在进行的或主动的动作。也可以说明被修饰词的性质和特征，此时可换成相应的定语从句。例如：
① There was a terrible noise following the sudden burst of light.
② He saw a flying bird and raised his bow.
③ I was satisfied with the exciting speech.
2. 现在分词作状语时，可作时间、条件、结果、原因和伴随状语，表示正在进行的或主动的动作。此时分词的逻辑主语就是主句的主语，因此要注意人称、时态和语态的一致性。例如：
① The visiting minister expressed his satisfaction with the talks, adding that he had enjoyed his stay here.
② European football is played in more than 80 countries, making it the most popular sport in the world.
③Seeing from the top of the hill, we can find that the city looks more beautiful.
3. 现在分词作补足语，表示正在进行的或主动的动作。例如：
① Soon they could see the steam rising from the wet clothes.
② The missing boys were last seen playing near the river.
4. 现在分词的独立主格结构作状语。例如：
① With his lips still trembling, he couldn't say a word.
②“ Mama! ” he cried suddenly, tears rolling down his cheeks. “妈妈！”他突然哭着喊，泪水从他的脸上流下来。（这里需要用现在分词的独立主格结构 tears rolling down his cheeks 作状语。）
③ Weather permitting, we'll go to the Great wall. 如果天气允许的话，我们就去长城。（这里需要用现在分词的独立主格结构 Weather permitting 作状语。）
二、过去分词
一、基本概念
1. 分词的定义
动词的-ed分词即过去分词，是由动词的过去分词构成，一般只有一种形式。
2. 过去分词的语法作用：
过去分词一方面具有动词的性质，另一方面也相当于一个形容词或副词，在句中可以作表语、定语、状语和补足语。
1) 过去分词作表语，主要表示主语的心理感觉或所处的状态。如：
Don’t touch the glass because it is broken. 不要碰那个杯子，它是坏的。
He is quite pleased with the design of the dress. 她很喜欢那礼服的式样。
2) 过去分词做定语：
单个的过去分词作定语一般放在名词的前面，相当于一个定语从句。如：
The excited people rushed into the building. 激动的人们奔进了大楼。
We need more qualified teachers. 我们需要更多合格的教师。
过去分词短语作定语通常放在被修饰的词后面，相当于一个定语从句。如：
Is there anything planned for tomorrow? 明天有什么活动吗？
The suggestion made by the foreign expert was adopted by the manager. 外国专家提出来的建议被经理采纳了。
过去分词作定语也可用作非限制性定语，前后用逗号隔开。如：
The books, written by Lu Xun, are popular with many Chinese people.这些书是鲁迅写的，受到了许多中国人民的喜爱。
The meeting, attended by one thousand students, was a success. 这次会议获得很大的成功，共有一千个学生出席了。
3) 过去分词做状语：
过去分词和-ing分词作状语一样，也可以表示时间、原因、条件、让步、方式或伴随情况等。
①表时间，相当于一个时间状语从句，有时过去分词前可加连词when或while来强调时间概念。如：
Seen from the top of the hill, the city looked like a big garden. 从山顶上看，这个城市就像一个大花园。
Accepted by the Party, he decided to devote his life to the cause of the Party.
入党以后，他决定献身于党的事业。
②表原因，相当于一个原因状语从句。如：
Deeply moved by the story, the excited people stopped quarrelling with each other.
激动的人们被那个故事深深地感动了，停止了争吵。
Encouraged by the speech, the young people made up their minds to take up the struggle.
受到了讲演的鼓舞，年轻人决定起来从事斗争。
③表条件，相当于一个条件状语从句，有时过去分词前可用if等词。如：
Given another chance, he will do better.再给他一次机会，他会做得更好。
Compared with your brother, you should make greater efforts to study English.
和你哥哥相比，你应该更加努力学习英语。
If heated, water can be turned into steam. 水如果被加热，会变成水蒸气。
④表让步，相当于一个though/although引导的让步状语从句。如：
Exhausted by the running, they went on running after the robber.
尽管已经跑得筋疲力尽，他们还是继续追赶着那个强盗。
Laughed at by many people, he continued his study. 尽管被许多人嘲笑，他还是继续他的研究。
⑤表方式或伴随情况。如：
The old man went into the room, supported by his wife.那个老人在他的妻子的搀扶下走进了房间。
Seated at the table, my father and I were talking about my job. 我和父亲坐在桌子旁边讨论着我的工作问题。
4) 过去分词作补足语：
过去分词可以在see, hear, notice, watch, find, get, have, feel, make, leave, keep等词后与一名词或代词构成复合宾语，用作宾语补语。如：
When will you go to the hospital and have your tooth examined? 你什么时候去医院检查你的牙齿？
When you are making a speech, you should speak louder to make yourself heard.
当你在作报告时，你应该讲响一点使自己被人听清。
当这类句子变成被动语态时，过去分词用作主语补语。如：
One of the glasses was found broken. 有人发现其中一个杯子破了。
They should be kept informed of the situation there. 应该让他们知道那儿的形势。

二、特别提醒
1. 过去分词作状语时，它的逻辑主语一般必须和句子的主语相一致。如：
When asked why he came here, the boy kept silent.当那个男孩被问到为何来这里时，他沉默不语。
Born and brought up in the countryside, he was interested in biology.
由于在农村出生并长大，他对生物很感兴趣。
如果过去分词的逻辑主语和句子主语不一致，必须使用过去分词的独立主格结构。
2. 动词have后所接的三种宾语补语：
have somebody/something do something 不定式作补语必须省去to, 不定式动作由宾语发出，表示一次性的动作。如：
I had the workers do the job for me. 我让工人们替我完成了工作。
Jim often has his father help him with his homework. 吉姆经常让他的父亲帮助做家庭作业。
have somebody /something doing something -ing分词作补语，分词动作也由宾语发出，强调动作的延续或正在进行。如：
They had the tractor working all the time. 他们让拖拉机一直工作着。
We won’t have the child talking to his mother like that. 我们不能让那个孩子那样对他的妈妈说话。
have somebody/something done 过去分词作补语，宾语和补足语之间有逻辑上的被动关系，通常有两种情况：
①主语让别人做某事，强调主语的意志。如：
He had his hair cut yesterday. 他昨天理发了。
Later on the center had a great many new trees planted.后来，这个中心让人种了很多树。
②主语遭到某种不幸或陷入恶劣的环境，说明宾语的一种无意识的被动行为。如：
He had his leg broken in the match last month.他在上星期的比赛中摔断了腿。
He had one eye lost in the war. 在战争中，他失去了一只眼睛。
3. 非谓语动词的被动式作定语的三种形式：
the bridge to be built 将要建造的桥 （表示将来的动作）
the bridge being built 正在建造的桥 （表示正在进行的动作）
the bridge built 造好的桥 （表示完成的动作）
4. 过去分词和–ing分词作表语的区别：
过去分词作表语通常表示主语所处的状态或感受，而-ing分词作表语多表示主语所具有的特征，如：
Hearing the news, we felt very surprised. 听到那个消息，我们感到很惊讶
The news is very surprising. 这个消息很令人惊讶。
They were frightened to hear the frightening sound. 他们听到那可怕的声音很害怕。
At the sight of the moving scene, all the people present were moved to tears.
看到这么动人的情景，所有在场的人都感动得流下了眼泪。
英语中这样的分词还有很多，如：amusing, amused; encouraging, encouraged; disappointing, disappointed; exciting, excited; puzzling, puzzled; satisfying, satisfied; worrying, worried; tiring, tired; pleasing, pleased; interesting, interested; astonishing, astonished等。
5. 过去分词和–ing分词作定语的区别：
过去分词作定语和-ing分词作定语有一定的区别。试比较下面几组短语：
boiled water开水 boiling water正沸腾的水
developed countries发展的国家 developing countries发展中国家
fallen leaves落叶 falling leaves 正在飘落的叶子
changed condition改变了的情况 changing condition变化着的情况
由此可见，过去分词作定语通常表示完成的或被动的动作；而-ing分词作定语可以表示正在进行的主动的动作。

参考资料：百度百科

Answer 3

拿 走路walk来说
原形 过去式 过去分词 现在分词
walk walked walked walking