Can I use single pictures of different English movies for teaching purposes?

This is similar to a question I just answered. I am reprinting here. The answer I gave to the other questioner:While copyright law is not my particular field of endeavor, the purpose of copyright law is to prevent theft. For-profit of another persons work product, namely the artistic production. There is a concept. However, that is known as "the fair use doctrine." As I understand this doctrine, it permits limited use of small parts of copyrighted material for educational purposes. That said, it might not be a bad idea to contact the agencies and/or studios that hold and/or protect the copyrights, present them with your proposal, and get written authority. That will eliminate any risk.