惟命是听
wéi​mìng​shì​tīng

to be at someone's beck and call

  1. 惟 wéi
    [particle]
    (literary) Used at the start or middle of a sentence to balance rhythm or adjust tone, without having a specific meaning; equivalent to 唯 wéi or 维 wéi in this role.
  2. 命 mìng nounverb
    order
    an instruction or command given by a superior
  3. 是 shì
    [object marker]
    (literary) a particle used to pull the object of a sentence to the front for emphasis
  4. 听 聽 tīng verb
    to obey
    to heed; to obey; to follow advice or a command