Why we still use the terms "sun rises" and "sun sets" when we know that it is the Earth that rotates around the Sun?

We use this term because it does describe how it looks, and after about 200 years it stuck. It would be bad grammar to say the sun is rotatinng to the other side of the Earth!It's just not done! ~Rome_Leader

"It would be bad grammar to say the sun is rotatinng to the other side of the Earth"
why would it be bad grammar? it wouldn't be correct but not because of the grammar... i'm I missing something?
what really is happening is the earth is rotating away from the sun.

To the lay observer, who does not know the facts, it would appear as though every day the sun rises from the east until noon, whereupon it sets westward. It took humans thousands of years to figure out that the sun was actually the center of our solar system (and still not the center of our universe as Copernicus would have liked to believe).

let's call it the West rotation sight!
kidding

Does morning break, does night fall or do clouds really burst? Sometimes we use visual imagery rather than hard science to describe our everyday world.
In this case, scientist also say "sunrise" and "sunset", but it is hard to think of an alternative that doesn't sound clumsy. I suppose technically, it isn't the sun that rises and sets but the boundary between light and dark on the earth, that is, the terminator line. I can't see "terminator rise" catching on though.

Why can't "lightrise" work?

Why not we replace these two terms straight away with Dawn and Dusk.