When yellow light falls on a sheet of paper that can absorb cyan, the yellow light will be partially absorbed by the paper, and the color that is reflected will be what we perceive.
Yellow light is a combination of red and green wavelengths. Since cyan absorbs red light, the red component of yellow will be absorbed, leaving the green component to be reflected. Therefore, the paper will appear green when yellow light is shined on it.
In summary, if yellow light falls on a sheet of paper that absorbs cyan, the paper will likely appear green.