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Don't put all your eggs in one basket.
Literal
Egg [object-を] all one [attributive-の] basket [into-に] put-don't.
A direct translation of the English proverb. The negative imperative ~な (attached to dictionary form) is the abrupt, direct 'don't do X' — harsh for most contexts but normal in proverbs, rules, and terse warnings. すべて is a formal 'all / everything,' more weighty than 全部.