难当重任
nán​dāng​zhòng​rèn

to be unable to handle a heavy responsibility

  1. 难 難 nán adjective
    difficult
    difficult; hard to do; troublesome; not easy; problematic; the opposite of 容易 róng​yì
  2. 当 當 dāng adjective
    to undertake
    To bear; to accept; to undertake responsibility
  3. 重 zhòng adjective
    important
    (bound form) important; significant; major
  4. 任 rèn nounverb
    post
    An official position or job; a responsibility or duty