[NTG-context] Understanding the basics of \define

Hello: I'm struggling with understanding the way \define is supposed to work. I would like to have a macros to generate tables and populate them with some specific data submitted as arguments. I apologize for my lack of understanding of the very basics, but e.g. the following code just doesn't compile: \define[1]\mytable{ \startxtable \startxrow \startxcell #1 \stopxcell \stopxrow \stopxtable} \mytable{abc} I would appreciate your help and maybe some references to read (if any) in order to educate myself. Kind regards, Pavel.