fan is a device for producing a current of air by the movement of a broad surface or a number of such surfaces.
fan helps to cool down the air
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Oven is used to bake cakes
Over is a cooking appliance
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Refridgerator helps to preserve the food.
Refridgerator helps to prevent the food from being spoiled.
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Computer helps to broden our horizen
Computer allows people to interact with one another more easily.