可数名词单数转化为复数的规则:
1、一般在词尾加s,如:Walkman—Walkmans  boy—boys
2、以sxshforget、ch结尾的名词,加es 如:dress—dresses(连衣裙)、bus—busesglass—glasses、box—boxesfax—faxeswish—wisheswatch—watches(手表)、peach—peaches
3、以辅音字母加y结尾,去yies,如diary—diariesfamily—familiesstudy—studies(书房)story—storieshobby—hobbiescountry—countries(国家)、butterfly—butterfliesfirefly—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—mangoesphoto—photoszoo—zoos  piano—pianos
5、以ffe结尾的名词,去ffeves  如:knife—knivesscarf—scarves(围巾)、theif—thieves(小偷)、 leaf—leaves(叶子)、housewife—housewives(家庭主妇)
6、不规则变化 child—childrenfoot—feettooth—teethpeople—people  fish—fishman—menwoman—womenpoliceman—policemenpolicewoman—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—playsstay—stays
2、以sxshcho结尾的名词,加es 如:dress—dresses(dress up装扮)wash—washes()catch—catchesbrush—brushes()touch—toucheswatch—watchesteach—teachesgo—goesdo—does
3、以辅音字母加y结尾,去yies,如try—tries(尝试)cry—cries()study—studies(学习)fly—fliescarry—carries()worry—worries(担心)
4、不规则变化 have—has
动词原形转化为动词ing形式(动词的现在分词、动名词)规则:
1、一般在词尾加ing,如ski—skiing(滑雪)、jump—jumpingeat—eatingclean—cleaning
2、以不发音的e结尾,去eing make—makingskate—skating(溜冰)take—takingwrite—writingcycle—cycling(骑自行车)
3、双写末字母加ing,如get—gettingrun—runningswim—swimmingshop—shoppingsit—sittingjog—joggingput—puttingplan—planning(制定计划)begin—beginningforget—forgetting(忘记)、stop—stopping
动词原形转化为动词过去式规则:
1、一般在词尾加ed,如:talk—talkedwater—watered
2、以不发音的e结尾,直接加d,如like—likedtaste—tastedlive—lived
3、以辅音字母加y结尾,去yied,如try—tried(尝试)cry—cried()study—studied(学习)carry—carried()worry—worried(担心)
4、双写末字母加ed,如stop—stopped
5、不规则变化
am\is—wasare—weredo—didhave—hadfly—fleweat—atemake—madego—wentsing—sangtake—tookcome—camesee—saw sit—satgive—gave buy—boughtget—gotforget—forgotmeet—mettell—toldrun—ran begin—beganrun—ranread—readput—putsay—said