Final answer:
Perspective is the method used to give a feeling of three-dimensionality in artwork.
Step-by-step explanation:
The method that is used to give a feeling of three-dimensionality is perspective. Perspective is a technique for representing three-dimensional space on a flat surface. It creates the illusion of depth and a sense of reality in artwork. By using perspective, artists can make objects appear closer or farther away based on their size and placement within the composition.