SYN: Preface, introduction, exordium, opening, introductory, part.

ANT: Close, termination, peroration, finale, conclusion.

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KEY: Precarious.

SYN: Hazardous, peril, ous, uncertain, riskful, unassured, insecure, dubious, doubtful.

ANT: Assured, certain, systematic, safe, immutable.

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KEY: Precaution.

SYN: Forethought, provision, premunition, anticipation, prearrangement, care, providence.

ANT: Carelessness, thoughtlessness, improvidence.