is still the main fuel source, carbon dioxide has to be emitted widely in order to maintain the health of the societies. The traffic congestion, in the same fashion, may not be reduced due to the rising oil price. The reason for this is the people who use cars will not choose the public transport if the tickets become more expensive with the increasing oil price. The reduction on pollution should not passively rely on some doesn't-really-matter factors, but it should be solved by more actively thinking of reusable energy sources and putting that into actions by converting the way that people live into a more sustainable and environmentally