ensure
- 01 B2 Upper Intermediate
to make sure that something happens or is true.
to make certain that a specific outcome, condition, or event occurs. Transitive — typically followed by a 'that' clause or a noun phrase.
Simple“Please ensure that all the windows are closed before you leave the house.”
In context“The new safety protocols were designed to ensure that no unauthorised personnel could access the laboratory after hours.”
UsageCommonly followed by a 'that' clause; in informal contexts, 'that' is often omitted.
Teacher's tipLearners often confuse 'ensure' with 'insure' (related to money/insurance) or 'assure' (to tell someone something to remove their doubt).
PitfallPlease ensure to lock the door. Please ensure that you lock the door.In formal writing, 'ensure' is usually followed by a 'that' clause rather than an infinitive with 'to'.
ensure vs insure vs assure — Assure is for people, ensure is for outcomes, and insure is for financial protection.
Usage ensure people · ensure safe · ensuring staff
“Passengers are being advised to check with their airlines ahead of time to ensure their flight is running or to see if there have been any schedule changes.”
“So, while it’s a good step in the right direction, many will still be waiting for appointments and may even have to resort to paying for them, ensuring the cita previa scam lives on.”
From Middle English ensuren, from Anglo-Norman enseurer, from Old French seur (“sure”). Doublet of insure.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.