They're your secret, though the pros will know where to look. Tell your story visually with just enough dialogue to fill in the cracks. Dip into the Working Unit of The Seminars about this business of Visual vs. Verbal Storytelling . Keep your lines of dialogue short. Even in the most play-like of films, dialogue is extremely brief.
American films are about what happens next.
The technology of cutting from one image to the next has a lot to do with this. European cinema is the only market for character studies similar to stage plays. Establish a strong Suspense Plot . Even in a romantic comedy. Film doesn't cope well with the mild suspense plots that work well in plays.