be动词有哪些分别怎么用

be动词的用法包括一般形式am、is、are.主语为第一人称“我”时用am.主语为第二人称时用are.主语是单三人称时用is。第三人称单数有哪些：1. 第三人称单数代词有：he, she, it。 如： How old is she? 她多大了？ Is he at home today? 今天他在家吗？ Is it your cat? 这是你的猫吗？2. 指示代词this, that。 如：Thats a Chinese car. 那是辆中国小汽车。This is my book. 这是我的书。3. 单数可数名词。如：Lucy, a cat, my book, an orange, the bag等。 如： Lucy is a good girl. 露西是个好女孩。Her father is a teacher. 她爸爸是教师。4. 不可数名词可被看作第三人称单数。如： There is some money in the purse. 在钱包里有些钱。5. 当数字或字母作主语时，看作第三人称单数。 如： “6” is a lucky number. “6”是个吉利数字。“I” is a letter. “I”是个字母。6. 数字的加、减、乘、除的结果常被看作第三人称单数。如：What is one and two? 一加二等于几？ Eight minus five is three. 八减五等于三。Be动词的用法口诀:我用am，你用are，is连着他，她，它；单数名词用is，复数名词全用are。变疑问，往前提，句末问号莫丢弃。变否定，更容易，be后not莫忘记。疑问否定任你变，句首大写莫迟疑。一.选择1.She _ Miss He.A.beB.amC.is2.I _ sorry.A./B.amC.are3.Here _ my ball.A.isB.areC.am4.You _ number eight.A.areB.isC.am5.What_this？A.isB.areC.be6.Helen_ a student.A.beB.amC.is7.Those _oranges.A.isB.areC.am8. Howold _yourteacher?A.beB.amC.is9. Where _ her mother?A.areB.isC.am10.Eric and Kathy _ my students.A.areB.isC.am11.Your books _ not good.A.isB.areC.be12.He_a boy.A.beB.amC.is13.It _ my dog.A.isB.areC.be14.Whose socks _ they?A.areB.isC.am15. _there any chairs in the classroom. A. IsB. AreC. Am16 .The man with big eyes _ a teacher.A.beB.amC.is17.How _ your father?A.isB.areC.be18.Mike and Liu Tao _ at school.A.areB.isC.am19.I_astudent.A.beB.amC.is20.They _ teachers.A.isB.areC.be21.This_my mother.A.areB.isC.am22._ you a student?Yes,I am.A.AmB.IsC.Are二.写出下列词适当形式:1.I am (缩略形式) _2.is (复数)_3.we are (缩略形式) _4.are not(缩略形式) _5.is not (缩略形式) _6.can not(缩略形式) _7.shes(完整形式) _8.its(完整形式) _9.theyre(完整形式) _10.dont(完整形式) _三.将下列句子变成否定句和一般疑问句1. His brother is a teacher.否定句:一般疑问句:2.Those are his parents.否定句:一般疑问句:3.Im 14 years old.否定句:一般疑问句:4.The ruler is on the table.否定句:一般疑问句:5.Tom is my teacher .否定句:一般疑问句:6.My shoes are 20 yuan .否定句:一般疑问句:7.This is a pen .否定句:一般疑问句:8.My name is Andy.否定句:一般疑问句:9.We are twins.否定句:一般疑问句:10.He is my brother.否定句:一般疑问句:11.I am a teacher.否定句:一般疑问句:12.She is my mother.否定句:一般疑问句