assure v. ensure v. insure

Assure, ensure, and insure all mean ‘to make certain’, but they are used in different contexts.

• Assure is applied to people, and it denotes positively informing someone of something in order to remove doubt.
• Ensure means ‘to guarantee’.
• Ensure and insure are sometimes interchangeable, but only insure means ‘to promise to reimburse if a specified risk occurs’.

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