gāo​lěi​shēn​qiàn

to build high walls and deep moats

  1. gāo adjective
    high
    high; tall; above average in height, level, or degree
  2. rampart
    A defensive wall or fortification used in military camps for protection
  3. shēn adjective
    deep
    deep; far from the surface or outside (physically or figuratively); having a large distance from top to bottom
  4. moat
    (bound form) a defensive ditch or trench; a moat around a city