可数名词单数转化为复数的规则:1、一般在词尾加s,如:Walkman—Walkmansboy—boys2、以s、x、sh、ch结尾的名词,加es如:dress—dresses(连衣裙)、bus—buses、glass—glasses、box—boxes、fax—faxes、wish—wishes、watch—watches(手表)、peach—peaches3、以辅音字母加y结尾,去y变i加es,如diary—diaries、family—families、study—studies(书房)、story—stories、hobby—hobbies、country—countries(国家)、butterfly—butterflies、firefly—fireflies(萤火虫)、city—cities(城市)4、以o结尾的名词,有些在词尾加es,有的加s,如:mango—mangoes、photo—photos、zoo—zoospiano—pianos5、以f、fe结尾的名词,去f、fe变v加es如:knife—knives、scarf—scarves(围巾)、theif—thieves(小偷)、leaf—leaves(叶子)、housewife—housewives(家庭主妇)6、不规则变化如child—children、foot—feet、tooth—teeth、people—people、fish—fish、man—men、woman—women、policeman—policemen、policewoman—policemen、snowman—snowmen动词原形转化为动词的第三人单数形式的规则1、一般在词尾加s,如:play—plays、stay—stays2、以s、x、sh、ch、o结尾的名词,加es如:dress—dresses(dressup装扮)、was