- 无声无息 wúshēngwúxī unnoticedhappening without making a stir; providing no news or information about progress
- 悄无声息 qiǎowúshēngxī noiselesslywithout making any sound; perfectly quiet
- 鸦雀无声 yāquèwúshēng absolute silenceA state where not a single voice or sound can be heard; complete stillness.
- 悄然无声 qiǎoránwúshēng silentabsolutely quiet
