곱씹어요 · 곱씹었어요 · 곱씹을 거예요 · 곱씹으세요
to chew over, to dwell on, to mull over; to chew repeatedly
Example
그는 친구가 한 말을 밤새 곱씹었어요.
He dwelled on what his friend had said all night.
Word parts
곱- 'double, again' (as in 곱절) + 씹다 'to chew'.
Good to know
Often used for dwelling on hurtful words or mistakes, while 되새기다 is more neutral or positive.