To reinforce (เสริมกำลัง) message or theme To set the mood To catch the interest of the audience To alert the audience To include narration(การบรรยาย): effective for training and educational application
To reinforce (เสริมกำลัง) message or themeTo set the moodTo catch the interest of the audienceTo alert the audienceTo include narration(การบรรยาย): effective for training and educational application