All the above are excellent. I find that my beginning students have a terrible time understanding correct exposure. Whether they shoot film or video, I suggest you devise repeated exercises on how to handle exposure in ALL kinds of conditions, including when the actor moves from shade to full sunlight. They need to do this over and over for the learning to sink in. We forget how many times we goofed until we learned how to do all this.
Just let your imagination play and you will never run out of exercises. Repeat, repeat, repeat.
Rick Wise
director of photography
San Francisco Bay Area
and part-time instructor lighting and camera
grad school, SF Academy of Art University/Film and Video
http://www.RickWiseDP.com
http://www.linkedin.com/in/rwise
email: Rick@RickWiseDP.com