you'd better believe it

Also, you better believe it. You may be assured, as in You walk ten miles every day?-You'd better believe it! This imperative is almost synonymous with you bet your ass. [Colloquial; mid-1800s]

Common Names:

Name	Pronounced	Usage
Silvijo	-	Croatian
MatyÁŠ	-	Czech
Philomela	-	Greek Mythology
Mafalda	mah-FAHL-dah (Italian), mə-FAL-də (Portuguese)	Italian, Portuguese
Piritta	PEE-reet-tah	Finnish
Kilian	KEE-lee-ahn (German)	German, Irish, French