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

cause; reason; a factor or condition that produces a result, often contrasted with 果 guǒ

Cannot help doing something; instinctively or involuntarily, often used in phrases like 不由得 bù​yóu​de or 不由自主 bù​yóu​zì​zhǔ