sure can be used as an adjective, most commonly to refer to something that is certain or confirmed.
It is often used to demonstrate one's assurance or confidence in the truth or validity of something. When used as an adjective, sure can also refer to something that is reliable or trustworthy.
'The results are sure to be positive.'
'We are sure of the outcome.'
'It is a sure thing.'
'He is a sure guide.'
'She is a sure ally.'
'This is sure evidence.'
When used as an adjective, sure should not be confused with the verb assure, which means to provide certainty or confidence to someone. It should also not be confused with the verb ensure, which means to guarantee or safeguard something.
sure is also an interjection, an exclamatory word used to express an emotion or to emphasize something.
When used as an interjection, sure is usually used to demonstrate a positive reaction to something or to show agreement.
'Sure, I’d love to help.'
'Sure, I believe you.'
'Sure, that sounds good.'
when used as an interjection, sure does not have any other meaning than the one above. It should not be confused with the verb assure, which means to provide certainty or confidence to someone. When used as an interjection, sure should be followed by a comma.