If we do not have oil or gas, how can we drive cars? Then we must walk everywhere. It is really tiring to do this. Someone will say, “Hey, you can ride a bike!” But if so, we can not move as fast as when we have cars.
It is 2011 now; energy resources are less than before. If we do not care about this, one day in the future the environment would be terrible.
Then lots of people started to think of creating something else to be another new energy source for us. For example, solar…
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