know for a fact

To have definitive knowledge of something. I know for a fact that he cheats in cards! I saw the ace up his sleeve. My mom says she knows for a fact that I'm getting the internship at her company, but I won't believe it until the recruiter calls me.

Common Names:

Name	Pronounced	Usage
Feri	-	Hungarian
Michael	MIE-kəl (English), MI-khah-el (German), MEE-kah-el (Swedish, Norwegian, Danish)	English, German, Swedish, Norwegian, Danish, Dutch, Czech, Biblical, Biblical Latin, Biblical Greek
Klement	-	Czech, Slovak
Sherrie	SHER-ee	English
Vinnie	VIN-ee	English
Mathys	-	French