He stayed tight-lipped about the company's financial problems.
Tips
history
From 《谷梁传·庄公三十二年》: 'when a matter is grave, one avoids it; when grave enough, one hides it entirely.' Originally about the historian's choice to suppress politically dangerous facts.
usage
The silence here implies the matter is sensitive, scandalous, or painful - not just that someone hasn't brought it up. Often paired with 对...讳莫如深 ('tight-lipped about X').
