You have a great many books on writing in general and screenwriting in particular to choose from, but if I could only take a dozen to a desert island for the rest of my writing life, I would choose these for instruction and inspiration:
Dancyger, Ken and Jeff Rush. Alternative Scriptwriting: Writing Beyond the Rules. Boston: Focal Press, 1995.
Dannenbaum, Jed, Carroll Hodge, and Doe Mayer. Creative Filmmaking From the Inside Out. New York: Simon & Schuster, 2003.
Egri, Lajos. The Art of Dramatic Writing. New York: Simon and Schuster, 1960.
Gibson, William. Shakespeare’s Game. New York: Atheneum, 1978.
Goldman, William. Adventures In the Screen Trade: A Personal View of Hollywood and Scriptwriting. New York: Warner Books, ...