Category 2: Vowel change, irregular ending, Past form=Past Participle
group 5: vowel change , d or t ending
creep crept crept
feed fed fed
feel felt felt
keep kept kept
kneel knelt \ kneeled knelt \ kneeled
meet met met
sleep slept slept
sweep swept swept
weep wept wept
leave left left
feed fed fed
feel felt felt
keep kept kept
kneel knelt \ kneeled knelt \ kneeled
meet met met
sleep slept slept
sweep swept swept
weep wept wept
leave left left
group 6: different pronunciation of the same vowel d or t ending
deal dealt dealt
dream dreamed \ dreamt dreamed \ dreamt
lean leaned \ leant leaned \ leant
leap leapt leapt
mean meant meant
read read (/red/) read (/red/)
hear heard heard
dream dreamed \ dreamt dreamed \ dreamt
lean leaned \ leant leaned \ leant
leap leapt leapt
mean meant meant
read read (/red/) read (/red/)
hear heard heard
group 7: ell turns to old
sell sold sold
tell told told
tell told told
group 8: vowel change with ought (or *aught) ending d or t ending
bring brought brought
buy bought bought
fight fought fought
seek sought sought
think thought thought
catch caught caught
teach taught taught
buy bought bought
fight fought fought
seek sought sought
think thought thought
catch caught caught
teach taught taught