1.无改变,过去式与原形相同。
let→let, put→put, hit→hit, must→must, set→set, beat→beat, cast→cast, cost→cost, cut→cut, hurt→hurt, read→red, shut→shut(shed→shed split→split spread→spread burst→burst)
2.元音字母的改变。
aw/ow/y→ew:draw→drew, blow→blew, grow→grew, know→knew, throw→threw, fly→flew
4.元音字母和子音字母都有改变。
(1) catch→caught, teach→taught
(2) sell→sold, tell→told, retell→retold
(3) can→could, will→would, shall→should
(4) say→said, pay→paid, lay→laid, relay→relaid
(5) sweep→swept, keep→kept, sleep→slept, creep→crept
(6) bring→brought, buy→bought, think→thought, fight→fought
5.子音字母改变