名词变复数的规则：1.一般的名词后可直接加S,例如,book-books;
2.以s,x,ch,sh,z结尾的单词后加es,例如,bus-buses;watch-watches;
3.以辅音字母加y结尾的,把y 变i加es,例如,baby-babies,lady-ladies;
4.部分以o结尾的单词后加es,例如,potato-potatoes,hero-heroes;
5.一般以f和fe结尾的单词要把f,或fe变为ves,例如,wife-wives,knife-knives;
6.还有一些不规则变化的,例如,man-men,child-children;
7.单复数同形的,例如,fish-fish,deer-deer;