문제 1
단답형
stop - ____________ - ____________ (빈칸 동일)
stop - ____________ - ____________ (빈칸 동일)
stopped

stop - ____________ - ____________ (빈칸 동일)
stopped
study - ______________ - _____________ (빈칸 동일)
studied
go - ____________ - gone
went
write - ______________ - written
wrote