Think-thought-thought
drink-drank-drunk
sit-sat-sat
lose-lost-lost
have-had-had
hear-heard-heard
sleep-slep-slep
find-found-found
say-said-said
fly-flew-flown
read-read-read
give-gave-given
tell-told-told
take-took-taken
understand-understood-understood
come-came-come
get-got-got(gotten)
wear-wore-worn
forget-forgot-forgotten