名词是什么？“名”就是名字，那么顾名思义，名词是表示人或物名称的词。
联系到我们的生活中，花草树木是名词，太阳月亮天体宇宙是名词，等等。
在句子中怎么用？需要掌握的重点难点一、可数名词的复数既然名词表示的是人或事物的名词，可数名词表示一个人或者一个物体时需要和冠词配合使用，那么表示两个或者多个人/事的时候有什么变化呢？不光要在前面加数量词，名词本身也要变成复数形式。
虽然名词变复数的情况五花八门，但也有一些规律可循，熟悉了这些规则，我们就掌握了一大半单词的复数形式。
1.规则名词复数形式①名词直接词尾加s变复数。
如：pen - pens apple - apples②以s, x, ch, sh, o结尾的单词加es变复数。
如：bus - buses watch - watches fish - fishes tomato - tomatoeshero，potato,tomato,Negro是加es，其他一般加s记住：Negroes and heroes eat tomatoes and potatoes. 黑人和英雄吃西红柿和土豆。
③以辅音字母+y结尾的单词，变y为i再加es.如：baby - babies factory - factories library - libraries④以f或fe结尾，去掉f或fe，变v再加es。
如：knife - knives wife - wives leaf - leaves life - lives shelf - shelves 注意：gulf, roof, chief, serf, belief, proof, handkerchief变复数加s。
口诀：海湾边、屋顶上、首领奴仆两相望；谁说他们无信仰，证据写在手帕上。
2.不规则名词的复数形式①改变单数名词中的元音字母。
如：foot - feet, man - men, tooth - teeth②结尾加en或者ren。
如：ox - oxen, child - children③表示“某国人”的单复数变化a, 单复数同形。
如：Chinese, Japaneseb, 词尾加s. 如：German - Germans, American - Americans, Roman - Romansc, 变man为men。
如：Englishman - Englishmen④复合名词的复数变化a.变中心词。
如： a son-in-law复数变成sons-in-lawb.在最后加s。
如：a grown-up复数变为grown-upsc.前后名词都变。
如：woman doctor复数变为women doctorsd.Boy/girl在前时，变后面的词。
如：a boy student复数变为boy students⑤有少数名词是单复数同形。
如：sheep, people二、不可数名词不可数名词包括物质名词和抽象名词，一般只有单数形式，没有复数形式。
但它们也有以下特殊形式。
1）物质名词和抽象名词借助单位词表示一定的数量。
如：a cup of tea a piece of paper a loaf of bread a piece of advice2）有些物质名词和抽象名词变成复数后意义有所不同。
如：air-airs神气 good-goods商品 paper-papers考卷 time-times时代三、常用国籍的单、复数归纳记忆：中国人和日本人单复数相同，英国人和法国人把a变成e，其余的在后面加s。
四、名词所有格,意思是“--的”名词单复数、所有格专项练习一、选择正确的答案1、I want three white paper.A、piecesB、piece ofC、pieces of2、Do you want to drink much ?A、a milkB、milkC、milks3、This is room. It’s very big.A、Lily and Lucy’sB、Lily’s and Lucy’sC、Lily’s and Lucy4、We visited house yesterday.A、TomB、TomsC、Tom’s5、Do you want some for supper?A、a potatoB、potatoesC、potatos6、In autumn，you can see a lot of on the ground.A、leafB、leafsC、leaves7、My sister has two . One is old，the other is new.A、a watchB、watchsC、watches8、Best wishes to you for Day!A、Teacher’sB、Teachers’C、Teacher9、Many children like to go to the Palace on Sunday.A、ChildrenB、Children’sC、Childrens’10、They come from Japan.They’re .A、JapaneseB、JapanesesC、a Japanese11、There are on the plate.A、two meatB、two meatsC、two pieces of meat12、Some are coming to help us.A、peoplesB、peopleC、the people13、Do you think the of buses is terrible?A、noiseB、voiceC、sound14、All the are made of ，not plastics.A、glass，glassB、glassese，glassC、glassese，glassese15、The horse has four .A、feetB、feetsC、foots16、Can you see many are eating the grass at the foot of the hill?A、sheepsB、sheepC、a sheep17、I saw quite a few walking in the street last night.A、GermenB、GermanC、Germans18、The two have been hidden among those trees.A、theifsB、thievesC、a thief19、——Jim，where were you last night?——At .A、Doctor Li’sB、Doctor LisC、Doctor Lis’20、Mr Green takes a after supper.A、20 minute’s walkB、20-minute walkC、20 minutes’ walk参考答案：CBABC CCBCA CBABA BCBAC二、用所给单词的正确形式填空.1、There’re ten living in this building.（family）2、In autumn fall form the trees.（leaf）3、A lot of visited our school last week.（policeman）4、The teach us how to pick apples.（farm）5、The plaza is full of .（visit）6、The shop sells . （radio）7、There are many different kinds of in the shop.（knife）8、Do you know who was the of the paper?（invent）9、The girl has just had an on her eyes.（operate）10、When I grow up，I want to be a .（science）参考答案：families leaves policemen farmers visitors radios knives inventor operation scientist三、写出下列名词的复数形式：1、bus2、class3、dress4、glass5、box6、match7、watch 8、tomato 9、radio10、photo 11、zoo 12、city13、family 14、country 15、factory16、party 17、story 18、baby19、day 20、way 21、key22、boy 23、life 24、knife25、leaf 26、German 27、Frenchman28、man 29、woman 30、Chinese31、Japanese 32、American 33、sheep34、foot 35、tooth 36、child参考答案：buses classes dresses glasses boxes matches watches tomatoes radios photos zoos cities families countries factories parties stories babies days ways keys boys lives knives leaves Germans Frenchmen men women Chinese Japanese Americans sheep feet teeth children四、用所给名词的所有格形式完成下列句子.1、——Are these dictionaries your （brother）?——No，they are my （father）.2、Excuse me，which is the way to the Hospital? （Children）3、——Whose are the rain coats?——They are the （students）.4、After my sister finished middle school，she went to the college.（teachers）5、——Is there anything important in newspaper?——No，there isn’t.（today）参考答案：brother’s father’s Children’s students’teachers’today’s。