1.一般情况下直接加er。如:short→shorter

2.以字母e结尾的形容词和副词加r。如:nice→nicer

3.以辅音字母y结尾的Y改为I加er。如:happy→happier

4.重读闭音节结尾的双写结尾辅音字母加er。如:fat→fatter→fattest

5.特殊变化：

good/well→better;

many/much→more;

ill/bad(badly)→worse;

little→less;

old(eld)→older/elder;

far→farther/further

6.多音节词:比较级在形容词.副词前面加more.

如:beautiful→more beautiful