It is at the center of our solar system. The Earth and other planets revolve around it. 

What is the axis? 

One whole spin of an object on its axis is called: 

In what direction does the Earth spin? 

How long does a revolution of the Earth around the sun take? 

What is an orbit? 

Earth's tilt (tilt = inclination) affects how much sunlight certain parts of the Earth receives. 

Which movement of the Earth has the SEASONS (Spring, Summer, Fall and Winter) as a consequence? 

When it's summer in the Northern Hemisphere, what season is in the South?