如果是过去式，那么要在单词的末尾加什么？

一般过去式构成： 表示一般过去式的动词通常用动词的过去式形式来表示，而动词的过去式是在动词原形的基础上变化的。动词的过去式可分为规则动词和不规则动词。规则动词的过去式变化如下：

一般情况下，动词词尾加 -ed 。

worked played wanted acted

以不发音的 -e 结尾动词，动词词尾加 -d。

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。

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。

stopped begged fretted dragged dropped planned dotted dripped

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

ed

应该是动词要用到过去分词

如:

I go to school;(一般进行时)

I went to school yeste