承蒙 (chéngméng) is a formal, humble expression used to acknowledge someone’s kindness, favor, or assistance — literally meaning 'to receive and be covered by' (承 = to receive/undertake; 蒙 = to be covered/blessed). Together, they convey deep gratitude and modesty, as if one is humbly sheltered under another’s goodwill. It is never used for self-praise or neutral statements — always in response to a benefit received.

This phrase appears almost exclusively in written or highly polite spoken contexts: formal letters, thank-you speeches, business correspondence, or respectful face-to-face acknowledgments (e.g., after receiving an invitation or recommendation). It typically introduces the favor or action that prompted gratitude — for example, 承蒙关照 (thanks to your care), 承蒙厚爱 (honored by your generous affection), or 承蒙推荐 (thanks to your recommendation). While grammatically a conjunction introducing a clause, it functions pragmatically like a polite preface to gratitude.