莫测高深 mò cè gāo shēn

DEFINITIONS

  1. enigmatic
  2. beyond one's depth
  3. unfathomable

CHARACTERS

莫 mò do not, is not, can not; negative
测 cè measure, estimate, conjecture
高 gāo high, tall; lofty, elevated
深 shēn deep; depth; far; very, extreme