悶聲不響 [闷声－响]

Jyutping mun6 sing1 bat1 hoeng2
Pinyin mēn shēng bù xiǎng

Definitions (CC-CEDICT)
  1. to keep silent
Definitions (Wiktionary)
  1. phrase, idiomatic
    to not say a word; to keep silent
    (syn.) 不言不語, 不言不语