（1）一般情况下,动词词尾加 ed ,如：worked played wanted acted （2）以不发音的 e 结尾动词,动词词尾加 d,如：lived moved decided declined hoped judged raised wiped （3）以辅音字母 + y结尾的动词,把y变为i 再加ed,如：studied tried copied justified cried carried embodied emptied （4）以一个辅音字母结尾的重读闭音节动词,双写词尾辅音字母,再加 ed,如：stopped begged fretted dragged dropped planned dotted dripped （5）注：不规则动词的过去式变化规律性不强,须多加记忆.go - went,make - made,get - got ,buy - bought ,come - came ,fly-flew ,is/am-was,are-were ,see-saw ,bring-brought,do-did,teach-taught,think-thought,say-said,sit-sat.read-read,spend-spent,eat-ate,give-gave,sit-sat,tell-told,write-wrote,feel-felt,find-found,hear-heard,know-knew,put-put,grow-grew,take-took,catch-caught,come-came,become-became,swim-swam,sweep—swept,sing—sang,draw—drew
比较级的构成规则
1．一般单音节词和少数以-er,-ow结尾的双音节词,比较级在后面加-er,最高级在后面加-est； （1）单音节词 如：small→smaller→smallest short→shorter→shortest tall→taller→tallest great→greater→greatest （2）双音节词 如：clever→cleverer→cleverest narrow→narrower→narrowest 2．以不发音e结尾的单音节词,比较级在原级后加-r,最高级在原级后加-st； 如：large→larger→largest nice→nicer→nicest able→abler→ablest 3．在重读闭音节（即：辅音＋元音＋辅音）中,先双写末尾的辅音字母,比较级加-er,最高级加-est； 如：big→bigger→biggest hot→hotter→hottest fat→fatter→fattest 4．以“辅音字母＋y”结尾的双音节词,把y改为i,比较级加-er,最高级加-est； 如：easy→easier→easiest heavy→heavier→heaviest busy→busier→busiest happy→happier→happiest 5．其他双音节词和多音节词（一个元音为一个音节）,比较级在前面加more,最高级在前面加most； 如：beautiful→more beautiful→most beautiful different→more different→most different tired→more tired→most tired (很重要,也很特殊) 注意：（1）形容词最高级前通常必须用定冠词 the,副词最高级前可不用.例句：The Sahara is the biggest desert in the world.（2） 形容词most前面没有the,不表示最高级的含义,只表示
