lcase$ - convert upper case to lower case
Lcase$ returns a copy of the string StrExpr in which each occurrence
of an upper case character has been replaced with its lower case equivalent.
The opposite conversion is performed by ucase$.
a$ = "The Party of the First Part partied in the First Part."
the party of the first part partied in the first part.
The Basmark QuickBASIC Programmerís Manual