1)单数名词加s:
students,
apples,
bags,
trees,
books,
brothers.?
2)以s、x、sh、ch结尾的名词加es:
glasses,
boxes,
brushes,
matches.?
3)以
辅音字母加y结尾的名词，变y为i加es:
cities,
babies,
enemies.?4)以f或fe结尾的名词，多数变f为v加es:
wives,
knives.但有些词只加s:
roofs,
proof
s,
chiefs.?
5)以o结尾的名词，有些加es:
Negroes,
heroes,
tomatoes,
potatoes.其它加s:
radio
s,
zoos,
pianos,
photos.?
6)不规则名词：foot→feet,
goose→geese,
tooth→teeth,
child→children,
man→me
n,
woman→women,
sheep→sheep,
deer→deer,
mouse→mice.
7)某些外来词变复数：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)复合名词变复数：以
不可数名词结尾的复合名词无复数形式，如：homework.?
以man或woman为前缀的复合名词变复数，前后两个名词都变复数，如：manservant→menservants,
woman
student
women
students.?
其它复合名词变复数：grown?up→grown?ups,
brother?in?law→brothers?in?law,
stand?by→stands?by.?
9)复合形容词做定语时，其中的名词保持单数：a
six?year?old
boy，a
two?hundred?page
book
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