Grammar: Nonfinite Verbs & Gerund（语法：非限定动词 (非谓语动词) & 动名词）
1. 非限定动词（非谓语动词）包括动名词、不定式和分词三种。
2. 非限定动词（非谓语动词）和限定动词的区别。
2.1 限定动词可在句中独立做谓语，非限定动词则不能。
2.2 限定动词的形式要与主语的人称、数一致，而非限定动词的形式则不受主语的人称和数的限制。
The girl walking in front is my sister.
The girls walking in front are my students.
Jim likes to sing.
I like to sing.
2.3 非限定动词具有双重性，从语法角度讲，它们不能像限定动词那样作谓语；但从意义上 讲，它们具有动词特征，既有动作的承受者（有自己的宾语），也有修饰其动作的副词，同 时还有时态和语态的变化。如：
Picking the grapes is the first step. (动名词有自己的宾语)
Running quickly is not easy. (动名词有自己的副词)
I am sorry to have troubled you. (动词不定式有时态变化)
I saw her carrying a book and going into the library. (分词有自己的宾语和副词)
3. 动名词：即语法上是名词，意义上是动词。可作主语、宾语、表语、介宾。
Getting up early is a good habit.
Being patient is important in making wine.
All children enjoy watching TV.
Stop talking and listen to me.
Seeing is believing.
His hobby is collecting stamps.
I am interested in speaking French.
She is good at telling lies.
3.1 动名词的否定结构：由not + 动名词组成。
Trying without success is better than not trying.
I must offer my apology for not coming to your party.
3.2 动名词的被动语态：有两种, 即 being + 过去分词和 having been + 过去分词。
Being invited to the party is a kind of honor.
Being criticized for breaking the vase made the boy ashamed of himself.
Having been made the leader of this team, he became arrogant.
3.3 动名词的复合结构：有物主代词或名词所有格加动名词构成。在此动名词结构中，物主代词或名词所有格是动名词动作的逻辑主语。如：
Do you mind my smoking?
Your joining in the game will be a great help.
The opening of the new building will eventually lead to women being allowed to have full membership of the Stock Exchange.
3.4 有些动词后必须要求动名词作其宾语。这类动词有：enjoy, appreciate,advocate, practice, acknowledge, admit, avoid, miss, escape, deny, fancy, imagine, consider, postpone, put off 等。
By taking a back street he escaped being seen.
The doctor first practiced using needles on his own leg.
Try your best to avoid running into trouble.
3.5 用于某些特殊句式
1) There is no use (good, sense) + (in) + -ING
There is no use advising him to give up smoking.
There is no good in drinking tea before sleeping.
2) feel like + -ING
I feel like sleeping.
I don’t feel like eating now.
3) have difficulty ( trouble, fun, a problem, a good time) + (in) + -ING
The student had no difficulty making money.
The children have a lot of fun listening to their mother telling stories.
He had had a good time talking with her.
4) be busy (worth) + -ING
The novel is worth reading.
The workers are busy selecting the best grapes on each vine.
5) spend + (in) + -ING
Tom had spent half a year preparing for the examination.
There is no sense spending so much money buying useless things.
6) How about + -ING
How about going to the movies?
How about inviting the Browns to our house tonight?