>can I say do form myform with @parm1, @parm2 in vfp7

Yes, you put LPARAMETERS or PARAMETERS as the first statement in the .Init() method of the form. Another useful technique is to save the parameters to form properties (which you predefine), so they don't go out of scope when Init() ends e.g.

* MyForm.Init()

LPARAMETERS ;
  tuParm1 ;
  , tuParm2

This.MyProperty1 = tuParm1
This.MyProperty2 = tuParm2

UPDATE: by default, DO ... WITH ... passes variables by reference, I'm not sure what prefixing them with "@" will do. If you want to pass variables by value, you can use DO ... WITH (parm1), (parm2) (enclosed in parentheses).

Variables passed to UDFs are by value by default, unless you prefix them with "@".

Arrays should be passed by reference, or you only get the first element.

Objects are always passed by reference.