Fuels when burnt in vehicles etc. produce harmfull gases like carbondioxide , methane , nitrogen, etc. into atmosphere . These pollute the air .This not only leads to pollution but also global warming ,depleation of ozone , acid rains etc.. Due to the excess burning of fuels oxygen content in air decreases . It will be a serious problem for all living beings also . So, we should decrease the use of fuels and use alternatives like using vehicle which run with solar energy and biological waste etc.
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