绞 ㄐㄧㄠ ˇ jiǎo 尽 ㄐㄧㄣ ˋ jìn 脑 ㄋㄠ ˇ nǎo 汁 ㄓ zhī 絞 ㄐㄧㄠ ˇ jiǎo 盡 ㄐㄧㄣ ˋ jìn 腦 ㄋㄠ ˇ nǎo 汁 ㄓ zhī to rack one's brains