▲所谓现在进行时，其实，本质上是，主系表（或称主补）句型。现在分词不是主语发出的谓语动词，而是形容词表示，主语的一种状态。而系动词 be 也不是助动词。 如 I am eating an apple. 中 eating an apple 是形容词性的，意思是说：我是处在正吃苹果的状态），am 是系动词。
——上面这段话，纯属无稽之谈。
正确的表述是：“be +现在分词”，构成进行时态。如：
She is looking after children. （现在进行时）不可转换说：Looking after children is she.
“系表结构”可以是“be +动名词（短语）”：be是系动词，动名词（短语）作表语。如：
Her job is looking after children.（主系表）可以转换说：Looking after children is her job.
▲你引用的帖子，除了有明显错误外，还把“现在分词”和“动名词”混为一谈。
严格来讲，从语法研究的视角看，这是两个截然不同的概念。
▲以下是我的原创，内容较多，对这个问题作了详尽的讲解和归纳。请你耐心阅读。

一、动名词和现在分词：两种不同概念的非谓语动词
■必修四的语法项目之一是“动词-ing形式”。在附录的语法专题中，是这样论述的：“动词-ing形式由动词原形+-ing形式构成。动词-ing形式能在句中作主语、宾语、表语、定语、宾语补足语和状语，但不能单独做谓语。”之后，列举了一些能作每种成分的例句。
显然，课本把动名词和现在分词混为一谈。把动名词和现在分词统称为“动词-ing形式”，表面来看，似乎简化了这两种术语和两个概念，把它们合二为一。但实际上，这是两个不同的事物，有着不同的语法特征和作用。尽管目前有的语法书包括教材在内，开始追逐时髦，更换术语，但是，我们做老师的，并不满足于这种说法。因为从国内外传统的语法观点来看，动名词(Gerund)和现在分词(The Present Participle)，应该有着自己独立的名称和语法特性，这是毋庸置疑的。
在第4单元，含有“动词-ing形式”的句子屡屡可见，如：
After half an hour of waiting for their flight to come, I saw people enter the waiting area looking around curiously. I stood for a minite watching them and then went to greet them.
由此看出，“动词-ing形式”在英语表达中，是十分常见的语言现象。
动名词是兼有动词和名词特征的非谓语动词，它是由表示动作的名词发展而来的。现代英语的动名词在古代英语(Old English)中都是表示动作的名词。到了中古英语(Middle English)以后，它的动词性增强了，但同时又保留了原有的名词特征。
■动名词由“动词+ing形式”构成，与现在分词同形。动名词几乎具备了名词的全部语法特征，同时又具有动词的某些特征，可以有自己的宾语和状语，有时态和语态变化等。
名词可以作句子的主语、宾语（包括及物动词宾语和介词宾语）和表语；名词前可以有名词所有格、物主代词修饰；名词可以作定语。同样，动名词也具备了上述功能。例如：
Watching a family of chimps wake up is our first activity of the day. 观看一家黑猩猩梦中醒来是我们那天的第一项活动。
Finding a job is difficult these days. 现在找工作不容易。
He hasn’t finished reading the science fiction. 他还没读完那部科幻小说。
Yuan Longping devotes all his energy to studying rice.袁隆平把他所有的精力献给水稻研究。
My favourite sport is playing tennis. 我最喜欢的运动是打网球。
His coming made me very happy. 他的到来使我很高兴。
We were annoyed by Mary’s crying. 我们对玛丽的哭叫感到恼火。
I bought a new writing desk yesterday. 我昨天买了一张新的写字台。
■然而，现在分词的语法作用是，跟助动词 be 连用构成进行时态；此外，现在分词的最主要功能是代替状语从句和定语从句，由此简化表达方式，在句中充当各种状语以及定语。例如：
1. 构成进行时态：
We are having an English lesson now. 我们现在正在上英语课。
The telephone is ringing.Would you answer it, please? 电话在响，你能接一下吗？
We were discussing the plan the whole morning yesterday. 昨天整个上午我们一直在讨论这个计划。
I was writing a letter when you phoned.你打电话时我正在写一封信。
2. 现在分词（短语）作状语：
现在分词（短语）作状语。在一个复合句中，当主句的主语跟从句的主语完全一致时，为了表达简练，我们可以把从句转换为分词短语形式，用以代替原来的从句。所以，现在分词（短语）可以表示时间、原因、方式、伴随、条件、结果、让步等。反过来，它又可以转换成相应的状语从句或并列句。
(1) 作时间状语：此时相当于when ,while或after等引导的时间状语从句。如:
Wandering in the street, she met an old friend of hers. = When she was wandering in the street, she met an old friend of hers.
Having finished their work, they had a rest. = After they had finished their work, they had a rest.
(2) 作原因状语：此时相当于because, since和as等引导的原因状语从句。如:
Not knowing English, he couldn’t understand the film. = Because he didn’t know English, he couldn’t understand the film.
Having taught in the school for many years, she knows her workmates very well. = Since she has taught in the school for many years, she knows her workmates very well.
(3) 作方式或伴随状语：作方式或伴随状语时，一般不能转化为状语从句，但可以转化成并列句。如:
My wife sat in the sofa, reading a magazine. = My wife sat in the sofa and read a magazine.
The boy came in, following his father. = The boy followed his father and came in.
(4) 作条件状语：此时相当于if等引导的条件状语从句。如:
Turning to the right, you will find a hospital. = If you turn to the right, you will find a hospital.
Going there by plane, you will arrive this night. = If you go there by plane, you will arrive this night.
(5) 作结果状语：此时相当于so that引导的结果状语从句。如:
He didn’t pass the exam, making his parents quite disappointed. = He didn’t pass the exam so that it made his parents quite disappointed.
(6) 作让步状语：此时相当于though/although，even if等引导的让步状语从句。如:
Weighing 50 kilograms, the box was carried away by him. = Though the box weighed 50 kilograms, it was carried away by him.
Admitting what he said, I still think that he hasn’t tried his best. = Although I admit what he said, I still think that he hasn’t tried his best.
■动名词和现在分词，因为语法书都有专门的讲解，所以有关细节问题本文不再赘述。本文拟从以下几个方面进行探讨：
1.动名词作定语和现在分词作定语
2.动名词作表语和现在分词作表语
3.动名词作表语和进行时态的区别
4.动名词作宾语和现在分词作状语
5.动名词的复合结构作宾语和现在分词作宾补
（一）动名词作定语和现在分词作定语
动名词和现在分词，都可以作前置修饰语（premodifier）修饰名词。同样是“动词-ing形式”作定语，被修饰语和修饰语之间的关系是否一样？ “动词-ing形式”作定语时，被修饰语和它的关系可能是“目的或用途关系”，也可能是“主谓关系”， 这两种不同的修饰关系，是区分动名词还是现在分词的试金石。如果是前者，那么就是动名词作定语；如果是后者，那么就是现在分词作定语。
【动名词作定语】
动名词作定语，说明动名词和被修饰语是“目的或用途的关系”。所以，我们可以用for doing，used for doing，或者which is used for doing来置换这个动名词，放在被修饰语之后作定语。例如：
a swimming pool
①→ a pool for swimming
②→ a pool used for swimming
③→ a pool with the purpose of swimming
限于篇幅，以下词组仅用第①种情况转换：
a walking stick → a stick for walking
a sleeping car → a car for sleeping
a waiting room → a room for waiting
a swimming pool → a pool for swimming
a washing machine → a machine for washing clothes
a writing desk → a desk for writing
a reading room→ a room for reading
a bathing cap→ a cap for bathing
a changing room→ a room for changing clothes
a sitting room→ a room for sitting
a watering can→ a can for watering flowers
a guessing game→ a game for guessing words
an ironing board→ a board for ironing clothes
a collecting tin→ a tin for collecting money
a hiding place→ a place for hiding
a racing bicycle→ a bicucle for racing
an operating table→ a table for operating
building materials → materials for building
a diving board→ a board for diving
reading materials → materials for reading
a closing speech→ a speech for closing a meeting
working hours→ hours (time) for working
a smoking room→ a room for smoking
a dancing hall → a hall for dancing
a washing machine → a machine for washing clothes
【现在分词作定语】
现在分词作定语，说明被修饰语和现在分词是“主谓关系”。既如此，就可以扩展为一个定语从句，该定语从句多为进行时态。例如：
a sleeping baby → a baby who is sleeping.
a barking dog→ a dog that is barking
flying birds → birds that are flying
smiling faces →faces that are smiling
a floating boat → a boat that is floating
falling leaves → leaves that are falling
boiling water → water that is boiling
the setting sun → the sun that is setting
the rising sun → the sun that is rising
the coming week → the week that will come
the following questions→ the questions that follow
running water → water that is running
a developing country→ a country that is developing
the suffering people → people who are suffering
a missing child→ a child who is missing
现在分词短语作定语，都是置于被修饰语之后。单个的现在分词作定语跟动名词作定语，一般都置于被修饰词之前。正确判断是哪种形式作定语，有利于我们理解词组甚至整个句子的准确含义。
但有时这种区别并不明显，比如a sewing machine（缝纫机）可以理解为a machine for sewing，或者a machine which can sew; a hunting dog（猎狗）可以理解为a dog for hunting，或者a dog that hunts。前一种解释是看作动名词，后一种解释是看作现在分词。
（二）动名词作表语和现在分词作表语
1. Her job is looking after children.
2. Her job is boring.
句1的意思是：“她的工作是照料孩子。”这是动名词短语looking after children作表语。因为is是系动词，主语和表语是平等的并列关系，所以可以互换而意思保持不变：Looking after children is her job.
句2的意思是：“她的工作很无聊。” 这是现在分词boring作表语，表明boring具备了形容词的作用。由于它是由使令性动词bore变化而来，具有很强的主动使令意味。所以，可以转换为一个主谓宾的句子：Her job bores her. “她的工作令她厌倦。”
因为动名词几乎具备了名词的全部语法特征，所以既然名词能作表语，那么动名词完全可以作表语。例如：
His hobby is collecting stamps. 他的业余爱好是集邮。
His ambition is working as a lawyer. 他的抱负是当律师。
The only way to cure your disease is going to bed. 治疗你的病的唯一办法是上床睡觉。
Her job is keeping the offices clean. 她的工作是给办公室保洁。
Her work is teaching children music. 她的工作是教孩子音乐。
His only wish is finding a job in an office. 他唯一的愿望就是找一份办公室的工作。
The ant queen’s full-time job is laying eggs. 蚁后的专职工作是产卵。
The boy’s hobby is playing games online. 这个男孩的爱好就是玩网上游戏。
My favourite sport is playing tennis.我最喜欢的运动是打网球。
Her first delight was going to the Tower. 她第一个想做的事情是参观伦敦塔。
以上例句中，主语和表语是平等的并列关系，所以可以互换位置而意思保持不变。例如：
His hobby is collecting stamps. 他的业余爱好是集邮。
→Collecting stamps is his hobby. 集邮是他的业余爱好。
His ambition is working as a lawyer. 他的抱负是当律师。
→Working as a lawyer is his ambition. 当律师是他的抱负。
The only way to cure your disease is going to bed. 治疗你的病的唯一办法是上床睡觉。
→Going to bed is the only way to cure your disease. 上床睡觉是治疗你的病的唯一办法。
现在分词作表语，说明该现在分词具备了形容词的作用。它表示句子的主语所具备的某种性质，这个性质是主动的，具备使令意味，让人发生情绪上的变化。
Tom’s progress in English is satisfying. 汤姆在英语上的进步是令人满意的。
The examination result is discouraging. 考试结果很令人沮丧。
Her facility in languages was surprising. 她在语言方面的才能令人吃惊。
The story about space travelling is interesting. 那个关于宇宙旅行的故事很有趣。
The film was boring to a degree. 这部影片非常枯燥。
The speed of the car was frightening. 这辆小汽车的速度真吓人。
The songs we heard last night were most inspiring. 昨晚我们听的歌曲很令人鼓舞。
The jokes he told us was amusing. 他给我们讲的故事很有趣。
It was amazing that he knew nothing about the event. 他对这个事件毫不知情，真让人感到诧异。
The service here is disappointing. 这儿的服务令人失望。
It is astonishing to me that he should be absent. 他竟然缺席,使我大为惊异。
That game was not very exciting. 那场比赛并不怎么精彩刺激。
The people upstairs are very annoying. 楼上的那些人非常吵闹。
The spelling of English is often puzzling. 英语的拼写常常使人伤脑筋。
The meaning of this word is confusing. 这个词的意思很令人费解。
I don't like making speeches in public; it's so embarrassing. 我不喜欢在公开场合演说，太难为情了。
My job can be very frustrating sometimes. 我的工作有时非常令人无奈。
The soft music sounds very pleasing to the ear. 那轻柔的音乐听起来十分悦耳。
The overall picture for farming is encouraging. 农业的总体形势是令人鼓舞的。
This work is tiring; it has tired me out. 这工作很累人，可把我累坏了。
Walking in the rain is really most fascinating. 雨中漫步的确非常令人陶醉。
The news from the front is very disturbing. 来自前线的消息令人极为不安。
The crawl of a snake is terrifying.  蛇爬行起来真可怕。
以上例句中的现在分词，说明主语具备了“使令”的意味：令人感觉如何。我们可以把这个分词转换为动词作句子的谓语，后面补上所缺的宾语。例如：
The service here is disappointing. 这儿的服务令人失望。
→ The service here disappoints us. 这儿的服务令我们失望。
Her facility in languages was surprising. 她在语言方面的才能令人吃惊。
→ Her facility in languages surprised us all. 她在语言方面的才能令我们吃惊。
The speed of the car was frightening. 这辆小汽车的速度真吓人。
→ The speed of the bus frightened the passengers. 这辆汽车的速度吓坏了乘客。
（三）动名词作表语和进行时态的区别
“动名词作表语”和“进行时态”形似而神异。请看这两个句子：She is looking after the children.和Her job is looking after the children. 它们太相似了，只是主语不同，其他成分完全一样，意思却大相径庭，这是为什么？
这确实是一个很有意思的问题。Her job is looking after the children. 意为 “她的工作是照料孩子的。” 本句中，is 是系动词，looking after the children是动名词作表语。因为is是系动词，主语和表语是平等的并列关系，所以，主语和表语可以互换而意思保持不变：Looking after the children is her job. 照料孩子是她的工作。
She is looking after the children. 意为“她正在照料孩子。”本句中，is是助动词，跟动词look的现在分词构成进行时态，所以is前后两部分不能互换。不可说：*Looking after the children is she. 又如：
His hobby is collecting stamps. 他的业余爱好是集邮。
→Collecting stamps is his hobby.
He is collecting stamps. 他正在集邮。
不可说：* Collecting stamps is he.
His ambition is working as a lawyer. 他的抱负是当律师。
→Working as a lawyer is his ambition.
He is working as a lawyer. 他正在以律师的身份工作着。
不可说：*Working as a lawyer is he.
【规律】A代表“主语”，B代表“动词-ing形式”：
“主系表结构”：A is B. 可以说：B is A. （is意为“是”）
“进行时态”：A is B. 不可以说：B is A. （is doing意为“正在做”）
请区别以下例句中，哪些是动名词作表语的例句，哪些是进行时态的例句。
His hobby is collecting stamps. 他的业余爱好是集邮。
His ambition is working as a lawyer. 他的抱负是当律师。
The only way to cure your disease is going to bed. 治疗你的病的唯一办法是上床睡觉。
Her job is keeping the offices clean. 她的工作是给办公室保洁。
Her work is teaching children music. 她的工作是教孩子音乐。
His only wish is finding a job in an office. 他唯一的愿望就是找一份办公室的工作。
The ant queen’s full-time job is laying eggs. 蚁后的专职工作是产卵。
The boy’s interest is playing games online. 这个男孩的兴趣就是玩网上游戏。
My favourite sport is playing tennis. 我最喜欢的运动是打网球。
Her first delight was going to the Tower. 她第一个想做的事情是参观伦敦塔。
The scientist is doing experiments no one has so far attempted. 科学家正在作一项迄今为止没人做过的实验。
According to these figures, our company is doing well. 从这些数字来看，我们的公司经营得不错。
The teacher is reading Tom’s English paper. 老师正在审阅汤姆的英语答卷。
He always makes careful notes while he is reading. 当他阅读时，他总是仔细作笔记。
The witness was telling about the whole accident. 目击者正在讲述整个事故的过程。
He is working in his photographic studio. 他正在摄影室工作。
The sculptor is working on a sculpture of Venus.  那个雕刻家正在雕一个维纳斯雕像。
（四）动名词作宾语，还是现在分词作状语？
首先，我们看两个句子：
1. Though it was raining hard, they went on working in the fields.
2. Though it was raining hard, they continued working in the fields.
句1，关于working in the fields是现在分词，还是动名词的问题，一直争论不休。所以有人给出了一个最好的办法，就是不要管它是什么，只需知道go on doing 即可。表面看来这是一个不错的主意，但实际上是混淆了现在分词和动名词的区别。从语言研究角度观察，这显然不够严谨，我们并不满意。其实，只要按照它们不同的语法作用进行分析。即可判断出它是现在分词，还是动名词。
我们知道，go on 这个词组中，go 是不及物动词，on 是副词，表示“继续”的含义（We use “on” to say that someone is continuing to do something）（注意：on 用作介词时不表示“继续”的意思）。例如：
They walked on in silence for a while. 他们继续默默无语地走了一会儿。
If the examination shows your company enjoys basically good health, read on. 要是审查表明你们公司的运营状况基本良好，请继续往下读。
He happened to be in England when the war broke out and he just stayed on. 战争爆发时他碰巧在英格兰，于是就留在那里了。
既然go是不及物动词，on 是副词，那么go on后面的“动词-ing形式”肯定不是“宾语”，而是“状语”表示伴随或方式。既然是状语，那么，working in the fields就是现在分词。
句2，continued是及物动词，后面需要宾语。因此，working in the fields是动名词作宾语。
以下例句是现在分词用在不及物的谓语动词之后，作伴随或方式状语：
The boy came running into the room, out of breath. 男孩跑着进了房间，气喘嘘嘘。（running为现在分词，作came的方式状语。即：“跑着进来”）
The visitor from Japan comes in smiling. 来自日本的客人笑着进来了。（smiling是现在分词，作somes的方式状语。即：“笑着进来”）
They also express their feelings using unspoken language through keeping physical distance, actions or posture.他们还通过使用无声语言，借助保持距离、动作和姿势，来表达感情。（using unspoken language为方式状语）
If you stand holding your arms across your chest, you may be protecting yourself. 假如你把双臂交叉放在胸前站着，那么你有可能在保护自己。（holding your arms across your chest为伴随状语）
He must be able to use the foreign language forgetting all about his own. 他一定要做到使用外语时，忘掉本族语。（forgetting all about his own为方式状语）
The children ran out of the room laughing and talking merrily. 孩子们愉快地笑着谈着跑出教室。（laughing and talking merrily为方式状语）
They eat using the fingers of their right hands. 他们使用右手的手指拿着饭吃。（using the fingers of their right hands为方式状语）
He came running back to tell us the news.他跑着回来告诉我们这个消息。（running为现在分词，作came back的方式状语。即：“跑着回来”）
The children came running when she called them. 她一叫唤，孩子们就跑过来了。（running为现在分词，作came back的方式状语。即：“跑着过来”）
I crossed the street to avoid meeting Tom, but he saw me and came rushing towards me .我穿过马路以便避开汤姆，但他看到了我并朝我跑过来。（rushing为现在分词，作came的方式状语。即：“朝我冲来”）
The leaves came raining down.树叶如雨般掉下来。（raining为现在分词，作came down的方式状语。即：“如雨一般下来”）
The bombs came raining down.炸弹雨点般落下。（raining为现在分词，作came down的方式状语。即：“如雨一般下来”）
■具备名词性质的动名词，可以作放在及物动词之后作宾语；但是，在不及物动词之后的“动词-ing形式”，则是现在分词作状语。
以下例句则是动名词作及物动词的宾语，不是状语：
He suggested spending the evening with a worker. 他建议跟一名工人一起度过那个晚上。
She couldn’t help laughing when she heard the joke. 听到那个笑话时，她禁不住大笑起来。
We don’t allow smoking here. 我们这儿不许吸烟。
He hasn’t finished reading the science fiction.他还没读完那部科幻小说。
We must practise speaking English. 我们必须练习说英语。
Sophia likes helping others and being helped.索菲娅喜欢帮助别人，也喜欢被帮助。
I first considered phoning him, but then decided to see him. 我开始想打电话给他，但后来决定见他。
Tom tried to avoid meeting her. 汤姆设法避免见到她。
Tom tried to avoid being met by her. 汤姆避免被她碰见。
除了作及物动词的宾语外，动名词还可作介词的宾语：
My parents objected to my marrying him. 我父母反对我与他结婚。
I’m looking forward to your coming. 我正盼望着你的到来。
My husband is fond of playing basketball. 我丈夫喜欢打篮球。
Yuan Longping devotes all his energy to studying rice. 袁隆平把他所有的精力献给水稻研究。
Thank you for giving us so much help yesterday. 谢谢你昨天给我们那么多帮助。
Little Lily was afraid of being left alone at home. 小莉莉害怕被单独留在家里。
We are all excited for having been praised. 我们都因受到表扬而激动不已。
（五）动名词的复合结构作宾语和现在分词作宾补
所谓“动名词的复合结构”，即是“含有逻辑主语的动名词”。
为了说明动名词表示动作的施事者，需要在动名词之前加上物主代词或名词所有格，这便构成了动名词的复合结构。动名词之前的物主代词或名词所有格形式即为其逻辑主语，但有时也可用人称代词宾格或名词的普通格。
（1）形容词性物主代词或名词所有格作逻辑主语：
当动名词的复合结构在句子中作主语时，其逻辑主语只能用物主代词或名词所有格。
His coming made me very happy. 他的到来使我很高兴。
Mary’s crying annoyed him. 玛丽的啼哭让他恼火。
（2）人称代词宾格或普通格形式作逻辑主语：
如果动名词复合结构作宾语，其逻辑主语可以用物主代词或名词所有格，也可以用人称代词宾格或名词的普通格。
She didn’t mind his (him) crying. 她不介意他的哭。
Is there any hope of Tom’s (Tom) winning the game? 汤姆有赢的希望吗？
What’s troubling us is their not having done away with so many cigarette ads. 烦扰我们的是他们没有消除过多的香烟广告。
（3）动名词的逻辑主语是无生命的东西，或虽然是有生命的东西但表示泛指意义时，只能用名词普通格。
Can you hear the noise of the sofa being dragged? 你能听见沙发被拖动的声音吗？
Have you heard of women playing football? 你听说过女的踢足球吗？
【判断正误】黑体部分是“动名词的复合结构”（即含有逻辑主语的动名词）。请给下列句子作个诊断。
第一组：
1.His asking questions is a good habit. (正确)
2. He asking questions is a good habit. (错误)
3. Him asking questions is a good habit. (错误)
4. Tom’s asking questions is a good habit. (正确)
5. Tom asking questions is a good habit. (错误)
第二组：
1. Do you mind his asking questions? (正确)
2. Do you mind him asking questions? (正确)
3. Do you mind he asking questions? (错误)
4. Do you mind Tom’s asking questions? (正确)
5. Do you mind Tom asking questions? (正确)
【分析】诊断已经给出，对错一目了然。“第一组”的5个句子是“动名词的复合结构”作主语，正确的句子只有两个：代词必须使用形容词性的物主代词，名词必须使用所有格形式，其他情况概不正确。“第二组”的5个句子是“动名词的复合结构”作宾语，正确的句子共有四个：只有代词主格是错的，其他形式都正确。
■讨论了“动名词的复合结构”之后，我们再看下面几组句子：
第一组：
1. Do you mind Tom opening the window?
2. I often see Tom opening the window.
【讲解】句1，opening the window是动名词作mind的宾语，Tom是逻辑主语。句子意思是“你介意汤姆打开窗户吗？”动名词的逻辑主语旨在特意强调这个动作的施事者，如果没有Tom，句中照常完整，但我们无法知道“谁要打开窗户”。句2，opening the window是现在分词做宾补，Tom是see的宾语。句子意思是“我经常看见汤姆开窗（这个情景）。”
第二组：
1. I can’t understand an adult scolding a little girl.
2. I was surprised to see an adult scolding a little girl.
【讲解】句1，understand是及物动词，scolding a little girl是其宾语，an adult是逻辑主语，句子意思是“我真不明白一个大人竟然辱骂一个小女孩。”加上逻辑主语an adult，旨在特意强调scolding这个动作的发出者。句2，scolding a little girl是现在分词做宾补，an adult是see的宾语。句子意思是“看见大人辱骂一个小女孩，我感到吃惊。”
第三组：
1. I still remember my mother taking me to the zoo for the first time.
2. Look at that little boy wandering about—perhaps he’s lost his mother.
【讲解】句1，remember是及物动词，之后经常接动名词作宾语，表示该动作已经发生过，所以taking me to the zoo for the first time为其宾语，my mother是逻辑主语。句子意思是“我仍然记得我妈妈第一次带我去动物园的情景。”加上逻辑主语my mother，旨在特意强调taking这个动作的发出者。
句2，首先看look at的用法。我们知道它可以跟宾语，,再跟宾补，宾补可以由不带to的不定式充当，也可以是现在分词。这句话中wandering about是现在分词，作宾语补足语符合语法要求。再看这句话的含义，它不是强调看“那个男孩”，而是强调“看一个情景（包括那个男孩和他正在做的事情）”。根据下文perhaps he’s lost his mother.更说明看的是“一个情景”，而非“那个正在徘徊的小男孩”。鉴于此，wandering about作宾补，而不是定语。
第四组：
1. The novel is about three sisters growing up.
2. The wallet was found by three pupils going home.
【讲解】句1，growing up是动名词短语作介词about的宾语，three sisters是growing up的逻辑主语。句子意思是“这部小说讲述了姐妹三人的成长历程。”如果动名词的逻辑主语是复数名词，通常用普通格而不用所有格。与前面不同的是，该句子中的动名词复合结构作了介词about的宾语。
句2，介词by后面也是跟了似乎是带有逻辑主语的“动词-ing形式”，但是，仔细分析则不然。going home是现在分词作后置定语（postmodifier），修饰three pupils，相当于定语从句who were going home。
总之，“动词-ing形式”用在名词之后，有可能出现如下三种情况：
1. “动名词复合结构”（即：含有逻辑主语的动名词）作及物动词或介词的宾语。
2. “动词-ing形式”为现在分词，作宾补。
3. “动词-ing形式”为现在分词，作定语，修饰前面的名词，相当于定语从句。
一般说来，在感官动词，如see, watch, notice, discover, hear, find, listen to, look at, feel和使役动词have, get, leave, keep等后面，这时的现在分词都是作宾语补足语。如：
Mary saw a stranger entering your office. 玛丽看见一个陌生人进入你的办公室。
I found a beggar standing at the door. 我发现一个乞丐站在门口。
I smelt something burning. 我闻到有东西烧煳了。
Don’t keep your children learning all day. 不要让你的孩子整天学习。
I heard someone knocking at the door. 我听见有人在敲门。
Don’t always keep the machine running. 不要老是让让机器转着。
■现在分词可以作状语（如方式、方面等），“介词+动名词”也可以用作状语。因此，有时在不改变句子意义的情况下，增添或减少介词便可以作为区分动名词和现在分词的标志。 有介词是动名词；没有介词是现在分词。为了简单起见，我们也可以不作进一步分析，只看作状语即可。例如：
Using his hybrid rice, farmers are producing harvests twice as large as before. 通过使用他的杂交稻种，农民现在生产的粮食是以前的两倍。（using是现在分词）
By Using his hybrid rice, farmers are producing harvests twice as large as before. （using是动名词）
They also express their feelings using unspoken language through keeping physical distance, actions or posture. 他们还通过使用无声语言，借助保持距离、动作和姿势，来表达感情。（using是现在分词）
They also express their feelings by using unspoken language through keeping physical distance, actions or posture.（using是动名词）
He must be able to use the foreign language, forgetting all about his own. 他一定要做到使用外语时，忘掉本族语。（forgetting是现在分词）
He must be able to use the foreign language through forgetting all about his own. （forgetting是动名词）
She caught cold (by) sitting on the grass. 她因坐在草地上面着了凉。
Mike wasn’t long (in) making up his mind. 迈克不久就会下定决心的。
I lost no time (in) talking. 我一刻也没耽误地谈话。
They spent a lot of time (in) searching for the ways to solve the problem. 他们花了大量时间寻找解决问题的办法。
We are busy (in) making arrangement for Christmas.  我们正忙着做圣诞节的准备。
以上例句，有介词时“动词-ing形式”是动名词；无介词时“动词-ing形式”是现在分词。