After the whiteboard is used for a period of time, it is normal that there are pen marks or ash deposits on the board surface; At this time, do not directly wipe the board surface with a rag (there are inevitably sundries and hard objects on the rag, which will scratch the board surface when wiping), but use white board cleaner, cotton cloth or paper towel to clean. The method is: spray white board cleaner on the board first, and then carefully wipe it with soft, clean cotton cloth or paper towel without hair.