刨 ㄆㄠ ˊ páo 根 ㄍㄣ gēn 问 ㄨㄣ ˋ wèn 底 ㄉㄧ ˇ dǐ 刨 ㄆㄠ ˊ páo 根 ㄍㄣ gēn 問 ㄨㄣ ˋ wèn 底 ㄉㄧ ˇ dǐ to dig up roots and inquire at the base (idiom); to get to the bottom of sth