When you do something complacently, you look pleased with how things already are — especially with something you have done — and you ease off. You stop pushing, stop checking, stop trying to make it better. The word is not a compliment. Teachers, bosses, and news writers use it when they think someone should wake up. It is not a warm “I’m happy for you.” It is closer to “You are sitting there looking too satisfied, and that is a problem.” You can smile complacently, lean back complacently, or talk complacently about a win as if nothing can go wrong now. Though actually, in real talk the scolding feeling often matters more than the tidy idea “they have stopped improving”: people use it for a smug, too-sure look even when nobody has clearly given up. It is a fairly formal adverb. In everyday speech people more often say you got too comfortable or too sure of yourself.

自滿地、沾沾自喜地