ANT: Extemporized, unprepared, unconcocted, unpremeditated.
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KEY: Precursor.
SYN: Forerunner, harbinger, herald, pioneer, advance-guard, cause.
ANT: Follower, consequent, result, effect, event.
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KEY: Precursory.
SYN: Prevenient, antecedent, introductory, prefatory, initiatory, prior, premonitory, prognosticative.
ANT: Subsequent, consequent, posterior, entailed, supervenient, eventual.
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