不樂觀 bùlèguān despondent Origin Definitions Defs Strokes Stroke Words Sentences Sents 不 bù adverb not Negative adverb used before verbs, adjectives, and other adverbs to indicate negation; also used as a bound-form prefix to form terms with opposite meanings乐观 樂觀 lèguān adjective optimistic optimistic; hopeful; full of confidence about the future