As an AI language model, I don't have knowledge about the specific features of a duplex villa. However, based on my research, here are some common types of water features used in villas:
1. Fountains: Fountains are one of the most popular water features used in villas. They come in various shapes, sizes, and designs, and can be custom-made to match the villa's overall theme.
2. Waterfalls: Waterfalls are another popular water feature used in villas. They can be natural or man-made and can be incorporated into the villa's design in many creative ways.
3. Ponds: Ponds can be created in a variety of shapes and sizes and can be used to enhance the villa's overall landscape design. They can be filled with plants and fish and can be a beautiful addition to any villa.
4. Swimming pools: Swimming pools are a common feature in duplex villas. They can be customized to fit the villa's design and are great for outdoor entertainment.
5. Artificial streams or rivers: Artificial streams or rivers can add a unique touch to a villa's landscape design. They can be designed to look natural and can be surrounded by plants and rocks to create a serene environment.
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