help please

[screen_name]

okay, im starting to use addtiledef and addtiledef2

now, i made one tile (16x16) for a grass tile

now how do i use addtiledef and addtiledef2 to replace the other grass tiles

i've tried using the x and y in pics1.png for the grass tile, the x and y in the level, and various other ways

can someone please explain please