how do we stay still when the earth is moving
The perception of motion is contingent upon a frame of reference. If you're riding in a car, and your friend is riding in another running in the same direction and speed as you, relative to each other it appears you're not moving. The only thing that tells you you are is the scenery around you slipping past. So although we spin around the center of the Earth, and the Earth revolves around the Sun, and the Sun revolves around the center of the Milky Way Galaxy, and the whole Galaxy is moving in a line away from others, it appears we're not moving. Our frame of reference on the Earth, where everything moves with us, suggests there's no motion.
The easy answer is that we don't stay still. We move along with the Earth. From our frame of reference, the Earth-human system does not seem to move. But from a third observer not on the planet, they'd see the planet revolving and rotating--and us rotating and revolving around with it.
we don't stay still when the Earth in moving. The earth is spinning at the speed of 900 miles per hour . Its a great speed you know. the normal passenger planes don't have this speed. But we don't feel that we are actually going at the speed of 900 miles per hour. You know why? Because the surface area of earth is very very huge. we are fraction of the earth so, we don't feel that we are moving so fast.
We don't! :-)
The earth spins on it's axis at 900 miles an hour, and we spin with it.
It travels in it's orbit around the sun at almost 20 miles a second, and we orbit with.
Our solar system turns around the centre of our rotating galaxy at 1,000,000 miles a day, and we turn with it.
And our whole galaxy is moving thorugh space at some huge speed mind-blowing speed, and we move with it.
We are not still at all!