有規則的有:
(1)直接在名詞後加s;
如orange—oranges;photo—photos;
(2)以x,s,sh,ch結尾的加es;
如:box—boxes;glass—glasses;waitress—waitresses;watch—watches;peach--peaches;
(3)以子音字母加y結尾的改y為i加es;
如:study—studies;library—libraries;hobby—hobbies;family—families;
(4)以f,fe結尾的改f,fe為v+es如:knife—knives;thief—thieves(注:以o結尾的我們學過的只有mango加es,mango—mangoes其餘加s,)。
不規則的有:
man—men;woman—women;people—people;child—children。