Be动词

be 动词有三种形式：am、is 和 are，具体使用视人称代词而定。请看下面的人称代词。
I  我	it 它
you 你	we 我们
he 他	you 你们
she 她	they 他们
注意，人称代词 you 既可作单数，也可作复数。
使用 am 搭配人称代词 I。 I am Tom.
使用 is 搭配人称代词 he、she 和 it. He is  an architect. She is an engineer. It is new.
使用 are 搭配代词 we、you 和 they。 We are roommates. You are new.你是新来的 They are architects.
缩写形式 I am =I'm He is =He's She is =She's It is =It's We are =We're/wɪr/ You are=You're/jʊr/ They are =They're  /ðer/
be 动词的否定 使用not 搭配 be 动词构成否定句。not 一词位于 be 动词之后。 I am a student. I am not a student. He is busy. He is not busy.   They are neat. They are not neat. neat adj 整洁的;
be动词的否定缩写 动词be否定形式的缩写有两种形式。第一种是缩写主格和动词be I am not a student. I'm not a student. She is not neat. She's not neat. We are not teachers. We're not teachers. 另一种方法是缩写 be 动词和单词 not。主格代词 I 不能采用这样方法 He is not a student. He isn't a student./ˈɪzənt/ 另一种方法是缩写 be 动词和单词 not。主格代词 I 不能采用这样方法 He is not a student. He isn't a student. They are not new students. They aren't new students. UK /ɑːnt/  US /ɑːrnt/  该句有连读
带be动词的问句 How are you today? Are you busy?你忙吗？
be动词引导的疑问句 为了构成含有 be 动词的是疑问句，将动词移至句首。记住在句尾加上问号 ( ? )。 He is a student. Is he a student? They are new.他们是新来的。 Are they new?他们是新来的吗？ You are busy.你们很忙。 Are you busy?你们很忙吗？
是非问句的简短回答 回答是非问句时，我们通常使用 yes 或 no 起头，后跟 be 动词形式的简短回答 Is he a student?Yes, he is. Is she new?No, she isn't. Is it 555-1212?No, it's not. Are they busy?      Yes, they are. Are they OK? 他们好吗？No, they aren't.   US /ɑːrnt/
含疑问词的疑问句 有些疑问句以 how 或 what 等疑问词起句。注意，疑问词位于 be 动词之前。 What's your name? How are you? What's your telephone number?/ˈtelɪfoʊn/ What's your last name?