标题: 新概念英语第一册语法解析五 [打印本页] 作者: saya 时间: 2012-9-26 15:10 标题: 新概念英语第一册语法解析五 情态动词的使用：can, must, may, might, need,1．情态动词can（能够）, must（必须）, may（可以） 结构：主语+can/must/may+动词原型
He can make the tea.
Sally can air the room.
We can speak English.
变疑问句将情态动词移到句首
Can he make the tea?
Can Sally air the room?
Can we speak English?
变否定句在情态动词后面加not
He cannot make the tea.
Sally cannot air the room.
We cannot speak English.
肯定回答及否定回答
Yes, he can. No, he cannot.
Yes, she can. No, she cannot.
Yes, we can. No, we cannot. 特殊疑问句：
What can you do? 注意：情态动词的句子没有第三人称单数的变化，不要在情态动词或动词后面加S。 2．Must/have to的区别
must 表示必须，是主观上觉得应该做，have to是不得不，是由于客观条件逼迫的必要要做
must 只能用在表示现在和将来的句子里，而have to do可以用在任何时态 3．must, may, might表示猜测：
must do 表示对现在事实的猜测
must have done表示对过去事实的猜测
must have been doing 表示对过去正在进行的事实的猜测
may/might do, may/might have done表示没有任何事实依据的猜测，might的可能性更小。
can’t/couldn’t 表示不可能 4．need 用法：
表示“需要”时为实意动词，后面可以加名词，也可以加不定式：
I need a pen. Do you need any beer? No, I don’t.
I need to have a rest.
Need doing=need to be done，表示被动
The flowers need watering.
Need在否定时做情态动词使用
You needn’t go so early. =You don’t need to go so early.
Must I clean the desk right now? No, you needn’t. there be 句型，be going to 结构 1. Be going to 结构，表示打算，准备，计划做某事 结构：主语+be动词+going to +动词原型
I am going to make a bookcase.
They are going to paint it.
The father is going to give the bookcase to his daughter.
变疑问句将be动词移到句首
Are you going to make a bookcase?
Are they going to paint it?
Is the father going to give the bookcase to his daughter?
变否定句在be动词后面加not
I am not going to make a bookcase.
They are going to paint it.
The father is not going to give the bookcase to his daughter.
肯定回答及否定回答
Yes, I am. No, I am not.
Yes, they are. No, they are not.
Yes, he is. No, he is not.
特殊疑问句
What are you going to do?
What are they going to do?
What is the father going to do?
2. There be 句型：表示哪里有什么东西(某处有某物) There is＋单数名词＋表示场所的词（一般为介词词组）
There is a book in this room.
There is a pen on the table
There are＋复数名词＋表示场所的词（一般为介词词组）
There are two pens on the table.
There are three schools there.
变疑问句将be动词移到句首
Is there a book in this room?
Are there two pens on the table?
变否定句在动词后面加not
There is not a book in this room.
There are not two pens on the table.
肯定回答及否定回答
Yes, there is. No, there is not.
Yes, there are. No, there are not.