名词复数的构成法：
1.一般在名词词尾加-s.如：dog-dogs,house-houses,gram-grams.
2.以-o或-s,-sh,-ch及-x结尾的名词加-es构成其复数形式.如：tomato-tomatoes,kiss-kisses,watch-watches,box-boxes,bush-bushes.
3.有些以-o结尾,是外来语或缩写名词,则加-s.如：piano-pianos,dynamo-dynamos,photo-photos,kimono-kimonos.
4.有些以-o结尾的名词,其-o前是元音字母则加-s.如：studio-studios,radio-radios.
以-oo结尾的名词只加-s.如：zoo-zoos.
5.以-y结尾的名词,且-y前是一个辅音字母,则把-y去掉,加-ies.如：baby-babies,university-universities,fly-flies,impurity-impurities.
如果以-y结尾的名词,-y前是一个元音字母,则直接加-s.如：boy-boys,donkey-donkeys.
6.以-f或-fe结尾的名词,一般将-f,-fe去掉,加-ves.如：wife-wives,wolf-wolves,calf-calves.
这类名词还有：life,knife,self,shelf,leaf,thief,sheaf,half等.
名词scarf,wharf,hoof,handkerchief的复数形式或加-s或去掉-f加-ves,即scarfs或scarves,wharfs或wharves,hoofs或hooves,handkerchiefs或handkerchieves.
也有些以-f或-fe结尾的名词只加-s.如：cliff-cliffs,belief-beliefs,safe-safes,roof-roofs,chief-chiefs等.
7.有些名词以改变元音构成其复数形式.如：man-men,woman-women,goose-geese,foot-feet,mouse-mice,louse-lice,tooth-teeth等.
child的复数为children,ox的复数为oxen.
8.有些表示生物的名词,其复数形式与单数相同.如：fish-fish,sheep-sheep,deer-deer.这类名词还有aircraft,means等
