1.现在式、过去式、过去分词同形（简称A-A-A型）
cost cost cost 花费
cut cut cut 割，切
hit hit hit 打
let let let 让
put put put 放下
read read read 读
hurt hurt hurt 伤
spread spread spread 传播
⒉现在式和过去式同形（A-A-B型）
beat beat beaten 打
⒊现在式和过去分词同形（A-B-A型）
come came come 来
become became become 变
run ran run 跑
4.过去式和过去分词同形（A-B-B型）
⑴在动词原形后加一个辅音字母d或t构成过去式或过去分词。
burn burnt burnt 燃烧
learn learned/learnt learned/learnt 学习
mean meant meant 意思
hear heard heard 听见
⑵把动词原形的最后一个辅音字母“d”改为“t”构成过去式或过去分词。
build built built 建筑
lend lent lent 借给
lose lost lost 失去
send sent sent 送
spend spent spent 花费
