An informal drawing or message on a public wall or surface, often done without permission.
The old wall was covered in graffito from people passing by.
那面舊牆被路過的人塗鴉覆蓋了。
Artwork made by scratching a design into a surface to show the layer underneath.
The graffito on the metal plate was created by scratching away the top layer.
金屬板上的塗鴉是通過刮掉頂層來創作的。