assure · verb T /əˈʃʊər/
assure (SAY WITH CERTAINTY)
B2 to tell someone confidently that something is true, especially so that they do not worry
Dictionary example:
She assured him (that) the car would be ready the next day.
Learner example:
If you decide to live in the capital, I can assure you there are plenty of sports facilities here, such as tennis courts, basketball courts, football fields, swimming centres and many more. (First Certificate in English; B2; Greek)
assure (MAKE CERTAIN)
C1 to make something certain to happen
Dictionary example:
This loan should assure the company's future.
Learner example:
The PT is guaranteed to assure higher test results or your money back! (Certificate in Advanced English; C1; Russian)