hold back
  阻礙,阻止,克制,抑制
  hold back
       v 1: hold back, as of a danger or an enemy; check the expansion
            or influence of; "Arrest the downward trend"; "Check the
            growth of communism in Sout East Asia"; "Contain the
            rebel movement"; "Turn back the tide of communism" [syn:
             check, turn back, arrest, stop, contain]
       2: keep under control; keep in check; "suppress a smile"; "Keep
          your temper"; "keep your cool" [syn: restrain, suppress,
           keep, keep back]
       3: wait before acting [syn: wait, hold off]
       4: secure and keep for possible future use or application; "The
          landlord retained the security deposit"; "I reserve the
          right to disagree" [syn: retain, hold, keep back]
       5: hold back; keep from being perceived by others; "She
          conceals her anger well" [syn: conceal, hold in]