GOSUB...RETURN
Statements
GOSUB transfers control to a GWBASIC
subroutine by branching to the specified line.
RETURN transfers control to the statement
following the most recent GOSUB (or
ON . .. GOSUB) executed, or to a specified line.
Syntax
linenuml
linenum2
7-120
GOSUB [linenuml] RETURN [linenum2]
is the first line number of the subroutine
is any line of your program different from linenum1 and
from the line number of the GOSUB statement