What causes seasons?

Seasons

 
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Seasons
by Anthony Gonzalez - Tuesday, 23 October 2012, 12:02 PM
 

I think that the seasons are because of the tilt of the earth.

Or the hemisphere affects it.

Or the sun changes the heat.

For some weird reason we are closer to the sun in winter but we are still cold and in June we are farther from the sun.