一、规则动词的过去式由“动词原形+-ed”构成,具体变化有：

1.直接在词尾加-ed.如:want—wanted,work—worked,need—needed,clean—cleaned

2.以不发音的e结尾的在词尾加-d.如：like—liked,live—lived,use—used,move—moved

3.以一个元音字母加一个辅音字母结尾的重读闭音节动词,先双写结尾的辅音字母,再加-ed.如：stop—stopped,trip—tripped

4.以辅音字母加y结尾的动词,先把y变成i,再加-ed.如：study—studied,carry—carried,hurry—hurried,marry—married

二、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