The document analyzes the use of different modes in the trailer for the film "Selma" and their impact on the audience. It discusses the repeated phrase "Enough is enough" which highlights the problem and spirit of the film. Written text on screen providing the location and date help audiences understand the context. Moving images such as barbed wire and gas masks suggest violence and tension. Sound effects like a gun shot make the trailer more realistic. Contemporary music near the end promotes the contemporary relevance of the issues raised.