费尽心思 fèi jìn xīn si

DEFINITIONS

  1. to rack one's brains (idiom); to take great pains to think sth through

CHARACTERS

费 fèi expenses, expenditures, fee
尽 jìn exhaust, use up; deplete
心 xīn heart; mind, intelligence; soul
思 si think, consider, ponder; final particle