现在分词的概念：

现在分词（PresentParticiple）(又称-ing形式)，是分词的一种，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）。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。

现在分词的用法：

1）做表语：
如：He was very amusing.
        That book was rather boring.
很多动词的现在分词都可以作表语：exciting, interesting, encouraging, disappointing, confusing, touching, puzzling.
2）作定语：
上面所出现的现在分词都可以用作定语,修饰一个名词：
如：That must have been a terrifying experience.
        I found him a charming person.
现在分词短语还可以放在名词的后面修饰名词,相当于一个定语从句：
如：There are a few boys swimming in the river.
        There is a car waiting outside.
3）作状语：
现在分词短语可以表示一个同时发生的次要的或伴随的动作：
如：Following Tom, we started to climb the mountain. 
        Opening the drawer, he took out a box.
        Taking a key out of his pocket, he opened the door.
现在分词短语还可以表示原因，相当于一个原因状语从句：
如：Not knowing her address, we couldn't get in touch with her.
        Being unemployed, he hasn't got much money.
现在分词短语还可以表示时间，相当于一个时间状语从句：
如：Hearing the news, they all jumped with joy.
        Returning home, he began to do his homework. 
        Jim hurt his arm while playing tennis.
        Be careful when crossing the road.
        Having found a hotel, we looked for some where to have dinner.
        Having finished her work, she went home.
4）作宾补：
现在分词在一些动词之后可以做宾语的补语：
例如：see, hear, catch, find, keep, have等。
如：I see him passing my house every day.
        I caught him stealing things in that shop.
        I smelt something burning.
        She kept him working all day.

现在分词其他用法解析：

1、现在分词一般式的用法：
现在分词的一般式所表示的动作与主语动作同时发生：
如：When we arrived, we found him sleeping. 我们到达时发现他在睡觉。
         Living in the 示的动作也可略早于或迟于谓语动作，但两者之间没有时间间隔：
如：Seeing nobody at home, he decided to leave a note. 发现没有在家，他决定留个字条。 
         He went home, finding the door locked. 他回到家，发现门是锁着的。当现在分词所表示的动作略迟于谓语动作时，现在分词通常位于句末。

2、现在分词完成式的用法：
现在分词的完成式主要表示发生在谓语动作之前的动作：
如：Having been there once, she knew the place quite well. 由于去过那儿一次，她对那地方很熟悉。
        Having failed twice, he didn't want to try again. 他已经失败了两次，不想再试了。
注：（1）现在分词的一般式和完成式均可表示已完成或先于谓语的动作，但有区别：现在分词所表示的动作虽然可以先于谓语动作，但两者之间没有时间间隔，而现在分词的完成式所表示先于谓语的动作则与谓语动作有一定的时间间隔：
如：Locking the door, he went out. 锁好门之后，他就出去了。
        Having invited him here to speak, we'd better go to his lecture. 既然我们请了他来作报告，我们最好去听一下。
有时即使是分词动作与谓语动作几乎同时发生，但如果要强调分词动作的完成性，也应用现在分词的完成式：
如：Having bought our tickets, we went into the theatre. 我们买好票后就走进剧场。
（2）现在分词的完成式一般不用作定语：
误：Do you know anyone having lost a cat? 你知道有谁丢了一只猫吗？
误：I want to talk to the person having broken the window. 我想同打破窗户的人谈谈。
若将以上现分词的完成式改为一般式也不可以（因为现在分词作后置定语时通常只表示与谓语动作同时或几乎同时发生的动作，而不能先于谓语动作而发生）：
误：I want to talk to the person breaking the window.

3、现在分词被动式的用法：
当要表示一个被动动作时，现在分词就用被动形式。现在分词的一般式和完成式均有被动式形式：
（1）现在分词一般式的被动式：主要表示现在正在进行的动作，也可表示与谓语动作同时发生的动作：
如：Who is the woman being operated on? 正在动手术的女人是谁?
         I saw him being taken away by the police. 我看见他被警察带走。
注：有时现在分词一般式的被动式所表示的动作也可发生在谓语动作之前（此时的现在分词通常用于表示原因，且多为状态动词）：
如：Not having a car, he finds it difficult to get around. 由于没车，她感到行动很困难。
（2）现在分词完成式的被动式：主要表示发生在谓语动词之前且已经完成的动作。
如：The subject having been opened, he had to go on with it. 话题已经开始了，他不得不谈下去。
        Having been written inhaste, the book has many mistakes. 这书因写得仓促，所以错误不少。
比较：Being so ill, she can't go to school. 由于病得那么严重，她不能去上学。
            Having been ill for a long time, he needed time to recover. 由于病了很长时间，他需要一段恢复的时间。

宾语从句的概念：

置于动词、介词等词性后面起宾语作用的从句叫宾语从句。宾语从句的语序必须是陈述语序。谓语动词、介词、动词不定式，v.-ing形式后面都能带宾语从句。有些形容词（afraid, sure, glad等）之后也可以带宾语从句。

宾语从句的用法：

1、宾语从句的引导词：
宾语从句通常由连词that和whether(if)、连接代词或连接副词以及关系代词型what引导：
如：We believe that he is honest. 我们相信他是诚实的。
         I don't know whether he'll arrive in time. 我不知道他是否能及时到。
         I don't know who(m) you mean. 我不知道你指谁。
        He asked why he had to go alone. 他问他为什么必须一个人去。
        Please tell me which you like. 告诉我你喜欢哪一个。
        She has got what she wanted. 她要的东西得到了。
注：有时介词后可接跟一个宾语从句(但介词后通常不接that和if引导的宾语从句)：
如：From what you say, he is right. 根据你所说的，他是对的。
有极个别介词(如but,except)可接that引导的宾语从句：
如：She remembered nothing about him except that his hair was black. 她对他什么都不记得，只记得他的头发是黑的。
2、宾语从句与形式宾语it：
当宾语从句后跟有宾语补足语时，通常在宾语从句处使用形式宾语it，而将真正的宾语从句移至句末：
如：I think it best that you should stay here. 我认为你最好住这儿。
       He hasn't made it known when he is going to get married. 他还没宣布他何时结婚。
3、连词that的省略问题：
引导宾语从句的连词that通常可以省略：
如：She said(that) she would come to the meeting. 她说过要来开会的。 
        I promise you(that) I will be there. 我答应你我会去。
注：有时为了强调，that引导的宾语从句可位于句首，此时that不可省略：
如：That she is a good girl I know. 她是一个好姑娘，我是知道的。
4、宾语从句与否定转移当动词think, believe, suppose, expect, imagine后接一个表示否定意义的宾语从句时，其否定通常转移到主语：
如：I don't suppose that it is true. 我认为那不是真的。
        I don't imagine that he will come. 我想他不会

使用宾语从句特别注意：

一、宾语从句的语序：
宾语从句的语序是陈述句语序即：连接代词/副词+主语+谓语+其他成分。
如：I don't know what they are looking for.
       Could you tell me when the train will leave?
       Can you imagine what kind of man he is?
二、宾语从句的时态：
主句是一般现在时，从句根据实际情况使用任何时态。
句：The headmaster hopes everything goes well.
主句是过去时态，从句须用过去时态的某种形式。
句：She was sorry that she hadn't finished her work on time.
当宾语从句表示的是一个客观真理或者事实时，即使主句是过去时，从句也用一般现在时态。
如：The teacher told his class that light travels faster than sound.
三、宾语从句的特点：
宾语从句可以作及物动词、介词及形容词的宾语。宾语从句的语序一律用陈述句语序。连接词that引导宾语从句在句中无词义，不充当句子成份，多数情况下可以省略。whether和if都可引导宾语从句，但whether后可紧跟or not；whether从句可作介词的宾语。如果从句太长，可以用形式宾语it.