（1）原形、过去式、过去分词相同：
cast/ cost/ cut/ hit/ hurt/ let/ put/ broadcast/
burst/ read/ red/ set/ shut/ spread/ thrust/ upset
（2）原形、过去式相同，过去分词不同：
beat/ beat/ beaten
（3）原形、过去分词相同，过去式不同：
come/ came/ come become/ became/ become
run/ ran/ run overcome/ overcame/ overcome
（4）原形不同，过去式，过去分词相同：
feel/ felt/ felt sleep/ slept/ slept
leave/ left/ left smell/ smelt/ smelt
keep/ kept/ kept creep/ crept/ crept
kneel/ knelt/ knelt sweep/ swept/ swept
spell/ spelt/ spelt weep/ wept/ wept
catch/ caught/ caught fight/ fought/ fought
teach/ taught/ taught think/ thought/ thought
stand/ stood/ stood lay/ laid/ laid
understand/ understood/ understood pay/ paid/ paid
bleed/ bled/ bled say/ said/ said
feed/ fed/ fed stick/ stuck/ stuck
lead/ led/ led strike/ struck/ struck
meet/ met/ met tell/ told/ told
learn/ learnt/ learnt sell/ sold/ sold
learned/ learned win/ won/ won
burn/ burnt/ burnt wind/ wound/ wound
burned/ burned have（has）/ had/ had
deal/ dealt/ dealt hear/ heard/ heard
mean/ meant/ meant lean/ leant/ leant
dream/ dreamt/ dreamt leaned/ leaned
bend/ bent/ bent shine/ shone/ shone
build/ built/ built shoot/ shot/ shot