Film Is Behavior

I've found with most young screenwriters, they try to tell their story through dialogue, through words, and not with action. What they don't understand is, film is behavior, creating an emotional situation that the character reacts to. When the story is told more with words than visuals, it makes for a bad, talky-talky screenplay, where the main character becomes very passive. The main character must always be active. He has to initiate the action.