um... help???

[empegs]

Hi, Im new here, so... hi.
Ok, Im doing a summer project for college, and although Ive been told what to do, Im still a little unsure. Id really appriciate any help anyone has to offer.
Ive been asked to comment on photo joiners by david hockney, and write about compostition, subject matter, use of light and dark, and texture. But Im not sure what these are or how they feature in Hockney's work.

Please, pleeeease help.