Definition
This idiom advises against being critical or unappreciative of a gift or favor that is offered; it suggests one should accept it gratefully without questioning its value.
莫辞謝、莫挑剔、莫求全責备（受贈時）
He offered free accommodation, so we should accept it; after all, never look a gift horse in the mouth.
他提供了免費住宿，所以我們應該接受；畢竟，不要對禮物吹毛求疵。
My boss gave me a free ticket to the concert, I guess I should just enjoy it, and never look a gift horse in the mouth.
老闆給了我一張免費的音樂會門票，我想我應該好好享受，不要對禮物吹毛求疵。
They gave us an old car, and although it isn't the newest, we shouldn't complain; never look a gift horse in the mouth, after all.
他們給了我們一輛舊車，雖然不是最新的，但我們不應該抱怨；畢竟，不要對禮物吹毛求疵。