不能不

bùnéngbù · HSK 5

cannot but

不能不 = not + able + not = double negative meaning must

Literal decomposition: 不 (not) + 能 (able/can) + 不 (not). Two negatives cancel into a strong positive — cannot not do it, so you have to. Common pattern: 不能不去 = cannot not go = must go.

不 — single pictograph; bird flying upward
Originally a pictograph in oracle bone script, traditionally interpreted as a bird flying up toward the sky and unable to come down, suggesting negation or refusal. Over time it became the standard negation word in Chinese, used before verbs and adjectives to mean 'not'.

能 — 厶 (head) + 月 (body/flesh) + 匕匕 (legs)
Originally a pictograph of a bear, showing its head, body, and powerful legs. Because bears were seen as strong and capable, the character was borrowed to mean 'ability' or 'can'. A new character 熊 (with the fire radical 灬) was later created for 'bear'.

不 — single pictograph; bird flying upward
Originally a pictograph in oracle bone script, traditionally interpreted as a bird flying up toward the sky and unable to come down, suggesting negation or refusal. Over time it became the standard negation word in Chinese, used before verbs and adjectives to mean 'not'.

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