动词过去式变化

【过去式的变化规则】
① 一般情况下,在动词原形后直接加ed.
如：wanted,played.
② 以不发音的字母e结尾的动词,直接加d.
如：hoped,lived.
③ 重读闭音节单词需双写最后一个辅音字母,再加ed.如：stopped, shipped.
④ 以辅音字母+y结尾的动词变y为i,再加ed.
如：studied,worried.
⑤ 有些动词不符合上面的规则,需要特殊记忆.
如：am(is)-was, are-were, go-went, eat-ate,
swim-swam, buy-bought, see-saw,
teach-taught, bring-brought, think-thought,
fall-fell, hurt-hurt, break-broke, win-won,
lose-lost