I don't know if this is universally true for all EF lenses or not....but.....EF lenses are marked with a small red dot. The EF-S lenses are marked with a white rectangle on the side.
If your friend is going to check out camera bodies, she may notice that there is both a small red dot and the white rectangle on where the lens mount is.
If there is both, then the camera body will be compatible with the EF lens and the EF-S lenses. She just needs line up the appropriate dots to mount the lens.