parties
不规则变化：man→men,woman→women,sheep→sheep,tooth→teeth,fish→fish,child→children,ox→oxen,goose→geese
不可数名词一般没有复数形式,说明其数量时,要用有关计量名词.如：a bag of rice→two bags of rice,a piece of paper→three pieces of paper,a bottle of milk→five bottles of milk.