规则动词的过去式变化如下：
一般情况下，动词词尾加ed ，如：
work—worked；play—played；want—wanted；act—acted
以不发音的 e 结尾动词，动词词尾加d，如：
live—lived；move—moved；decide—decided；decline—declined；hope—hoped；
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
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-fo und,hear-heard,know-knew,
put-put,grow-grew,take-took,catch-caught,come-came,become-became,swim-swam ，sweep—swept，sing—sang，draw—drew，
以上的（1）至（4）条中的发音均有改变，具体分别有/d/ /t/ /id/。
规则动词词尾加-ed有三种读音：
1. 在清辅音后读作[t]。如：asked, helped, watched, stopped
2. 在浊辅音和元音后读作[d]。如：enjoyed, studied, moved, called
3.在t / d后读作[id]。如：wanted, needed
不规则动词的过去式大体上归纳有以下六条记忆法：
1. 以t结尾的词，过去式与原形相同。如：put—put, let—let, cut—cut, beat—beat
2. 以d结尾的词，把d变成t。如:build—built, lend—lent, send—sent, spend—spent
3. 以n结尾的词，在词后加t。如：mean—meant, burn—burnt, learn —learnt
4.以ow / aw结尾的词，把ow / aw变成ew。如：blow—blew, draw—drew, know —knew, grow—grew
5.含有双写字母的词，将双写改为单写，在词尾加t。如：keep—kept, sleep—slept, feel—felt, smell—smelt
6.含有元音字母o / i的词，将o / i变成a。如：sing—sang, give—gave, sit—sat, drink —drank
但也有例外，如get的过去式是got，与第一条不符，仅仅是大多数动词符合。
不规则变化动词表：
原形过去式过去分词
be was/were been
begin began begun
bring brought brought
buy bought bought
catch caught caught
come came come
cut cut cut
do did done
draw drew drawn
drink drank drunk
drive drove driven
eat ate eaten
feel felt felt
fight fought fought
find found found
fly flew flown
get got got
give gave given
go went gone
grow grew grown
have had had
hear heard heard
