1)單數(shù)名詞加s:students,apples,bags,trees,books,brothers.
2)以s、x、sh、ch結(jié)尾的名詞加es:glasses,boxes,brushes,matches.
3)以輔音字母加y結(jié)尾的名詞,變y為i加es:cities,babies,enemies.4)以f或fe結(jié)尾的名詞,多數(shù)變f為v加es:wives,knives.但有些詞只加s:roofs,proof s,chiefs.
5)以o結(jié)尾的名詞,有些加es:Negroes,heroes,tomatoes,potatoes.其它加s:radio s,zoos,pianos,photos.
6)不規(guī)則名詞：foot→feet,goose→geese,tooth→teeth,child→children,man→me n,woman→women,sheep→sheep,deer→deer,mouse→mice.
7)某些外來詞變復(fù)數(shù)：datum→data,medium→media,bacterium→bacteria,curriculum→curricula,criterion→criteria,phenomenon→phenomena.um/?on→a)?analysis→analyses,basis→bases,crisis→crises,diagnosis→diagnoses.is→es
8)復(fù)合名詞變復(fù)數(shù)：以不可數(shù)名詞結(jié)尾的復(fù)合名詞無復(fù)數(shù)形式,如：homework.
以man或woman為前綴的復(fù)合名詞變復(fù)數(shù),前后兩個(gè)名詞都變復(fù)數(shù),如：manservant→menservants,woman student women students.
其它復(fù)合名詞變復(fù)數(shù)：grown?up→grown?ups,brother?in?law→brothers?in?law,stand?by→stands?by.
9)復(fù)合形容詞做定語(yǔ)時(shí),其中的名詞保持單數(shù)：a six?year?old boy,a two?hundred?page book