極深研幾 jí shēn yán jǐ

DEFINITIONS

  1. deep and detailed investigation (idiom)

CHARACTERS

極 jí extreme, utmost, furthest, final
深 shēn
HSK 4
deep; depth; far; very, extreme
研 yán
HSK 4
grind, rub; study, research
幾 jǐ how many? how much?; a few, some