名词单数
名词单数变复数规则：
1. 单数名词词尾加s
例：map→maps ，boy→boys ，horse→horses ，table→tables
2. s , x , sh , ch结尾的词加es
例：class→classes , box→boxes , bus→buses ,dish→dishes
3.以o结尾的词,变复数时有生命加es。无生命加s
hero→heroes ,negro→negroes ,
tomato→tomatoes，potato→potatoes
4. 以辅音字母加y结尾的名词,变y为i,再加es。以元音字母加y结尾的直接加s
例：family→families , city→cities, party→parties
5. 以f或fe结尾的名词,变f或fe为v,再加es。
例：shelf→shelves , wolf→wolves , life→lives , knife→knives
6.以ce, se, ze, (d) ge等结尾的词加s,读|z|
7. 名词复数的不规则变化：
（1）child→children woman→women an Englishman→two Englishmen
（2）单复同形 deer，sheep，fish，Chinese，Japanese， species，means , Swiss
除人民币，美元、英镑、法郎等都有复数形式。如: a dollar, two dollars; a meter, two meters
（3）集体名词，以单数形式出现，但实为复数。
people police cattle是复数
（4）以s结尾，仍为单数的名词
maths，politics，physics是单数。news是不可数名词。
（5) 表示由两部分构成的东西，
glasses（眼镜） trousers （长裤） clothes （衣服）
（6） 另外还有一些名词，其复数形式有时可表示特别意思
goods （货物） waters （水域） fishes （各种鱼）
将下列句子变成单数形式：
1) Do the girls like the flowers?
2) These geese have big feet.
3) The black mice look terrible.
4) Those cooks don't need new knives.
5) The Dutchmen are running after two thieves.
6) The Americans work hard.
7) These pairs of trousers are too short for the boys.
8) The babies need three glasses of milk.
9) The countries are going to have two more big factories.
1.Does the girl like the flower?
2.This goose has big feet.
3.The black mouse looks terrible.
4.That cook doesn't need new knif.
5.A Dutchman is running after one thief.
6.The American works hard.
7.This trousers is too short for the boy.
8.The baby needs one glass of the milk.
9.The country is going to have one more big factory.
