动词过去式和过去分词法则
（一）、不规则动词过去式和过去分词
动词的过去式和过去分词是初中英语教学中的重点,而有些动词的不规则变化是这些重点中的难点,但这些不规则变化也不是毫无规律可循的.现将初中英语中一些常用的不规则动词变化介绍如下.
一、原形、过去式和过去分词的词形和读音都相同的单词,结尾字母一般是t或d.如：
cut-cut-cut,hit-hit-hit,put-put-put,cost-cost-cost,let-let-let,shut-shut-shut,set-set-set,hurt-hurt-hurt,spread-spread-spread
特殊：动词read的过去式和过去分词虽然词形与原形一致,read-read-read,但发音分别是[ri:d]-[red]-[red].
二、有些动词的过去分词与原形是一样的.如：
come-came-come,become-became-become,run-ran-run,overcome-overcame-overcome
三、有些动词的过去式和过去分词相同.如：
1.把单词结尾的字母d改为t.如：
lend-lent-lent,spend-spent-spent,send-sent-sent
2.改变单词中间元音字母.如：
sit-sat-sat,win-won-won,shine-shone-shone,hold-held-held
3.以eep结尾的动词,把eep改为ept.如：
keep-kept-kept,sleep-slept-slept,sweep-swept-swept
4.过去式和过去分词都以augh或ough结尾的动词.如：
buy-bought-bought,fight-fought-fought,think-thought-thought,bring-brought-brought,teach-taught-taught,catch-caught-caught
5.有的以ay结尾的动词,在过去式和过去分词中把ay变成aid.如：
say-said-said,lay-laid-laid,pay-paid-paid
6.另有一些其它形式的变化.如：
have-had-had,learn-learnt-learnt,leave-left-left,lose-lost-lost,make-made-made,meet-met-met,feel-felt-felt
四、有些动词原形中含有字母i,在过去式中变i为a,在过去分词中变i为u.如：
五、以字母ow或aw结尾的动词,在变成过去式时,通常把元音字母变成e,在变成过去分词时,通常只在词尾加n.如：
blow- blew- blown,draw-drew-drawn,grow-grew-grown,throw-threw-thrown,know-knew-known
六、有些动词的过去分词是在原形词尾加n或en,变成以en结尾的单词.如：
rise-rose-risen,give-gave-given,take-took-taken,fall-fell-fallen,drive-drove-driven,eat-ate-eaten
特殊：write-wrote-written,speak-spoke-spoken,ride-rode-ridden,get-got-gotten
（二）、动词过去式和过去分词的变化规则
动词过去式和过去分词有规则变化和不规则变化两种.
1) 规则变化
情况 例词 读音与说明
动词原形 过去式 过去分词
一般在动词原形后加-ed look
call
open
need looked
called
opened
needed looked [lukt]
called [kC:ld]
opened [5EupEnd]
needed [ni:did] ①-ed在清辅音音素后
发音为〔t〕,在浊辅音后发音为〔d〕,在元音后发音也为[d]
②-ed在〔t]、〔d〕
后发音为[id]
③但fix的过去式和过去