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There are various ways you can accomplish this, with strategic placement of furniture and decorating tips. For example, if you want to divide a large livingroom/dining room area, you can place a sofa or loveseat with it's back to the entrance of the livingroom, behind (backing up to) the dining room table and chairs, and this will indicate that you are entering a 'different' room. Some people put up 'dividers' that are decorative and fashionable, like for example, a 'half' (low) wall coming out of each side of the bordering walls of the room, creating an 'entryway' into the other room. They can be painted a different/coordinating color, covered with wallpaper, mirrored, etc., to fit in with your existing decor. You can also place some 'tie-back' draperies on either side of the walls to 'indicate' this is a separate room. It all depends on your actual set up, decor, and which one room you would like to divide into two smaller ones.
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