Sure: free from doubt as to the reliability, character, action, etc., of something; confident, as of something expected; convinced, fully persuaded, or positive; assured or certain beyond question; worthy of confidence; reliable; stable.
Synonym: assured, certain, confident, reliable, effective, undoubted, guaranteed.
Example: Are you sure of what you are saying?
Usage in Sentence: Sure of, not for.
Don’t say: I’m quite sure for her honesty.
ü Say: I’m quite sure of her honesty.