ENGLISH
REFERENCE

ensure

v.
B2 Upper Intermediate Oxford US //ɛnˈʃʊɹ// UK //ɛnʃˈɔː// en·sure Academic Archaic General-service

v. to make sure that something happens or is true. You use this when you want to guarantee a specific result.

v. to make certain that a particular outcome or condition will occur. Transitive; often followed by a 'that' clause or a direct object.


SIMPLE

Please ensure that all the windows are closed before you leave.

CONTEXTUAL

The new safety regulations are designed to ensure the protection of every worker on the site.

COMPLEX

To ensure the longevity of the historical documents, the museum maintains a strictly controlled environment with specific levels of humidity and light.

Synonyms
Origin

From Middle English ensuren, from Anglo-Norman enseurer, from Old French seur (“sure”). Doublet of insure.

Usage

The verb is transitive and frequently takes a 'that' clause as its object. In formal writing, 'that' is usually retained rather than omitted.

Pitfall

I will ensure you to get a seatI will ensure that you get a seatEnsure cannot be followed by an object + infinitive; it requires a 'that' clause or a direct noun object.

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