1、直接加-s.
如：tree-trees樹,desk-desks桌card-cards, parent-parents,
2、以s,x, ch, sh 結尾的.加es.
如：bus-buses, box-boxes, watch-watches 手表bai, brush-brushes 刷子, glass-glasses.
3、以輔音字母+ y結尾的，改y為i再加es.
如：country-countries 國家、鄉村, city-cities 城市, baby-babies, family-families,
特例：：boy-boys, monkey-monkeys, toy-toys, play-plays(劇本)
4、以f或者fe 結尾的詞，改f為v,再加es.
如：knife-knives刀, leaf-leaves 樹葉, wife 妻子-wives.
5、以O結尾的單詞,有生命的+-es,無生命+s.
如：Hero-heroes 英雄, Negro-negroes 黑人, potato-potatoes 土豆, tomato-tomatoes 西紅柿