don't add any background that is not in input image.
expand background if needed.
copletely remove the subject in the background
remove background really
Change realistic background
Remove everything apart from the background.
remove background
remove the main character of the image and leave the one in the background.
Background add light
Blurred green and yellow background
put white background
totally black background,
Light the background and need clear image
Back ground appears on nature hill city