一般情况下,动词词尾加 -ed ,如：
worked played wanted acted
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
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
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