switch colours

[melon]

I'm sure it's simple but ...

I don't know how to! ;-)

I've got two words: Let's say "one" and "two".
(These two words are links and each's from a different class (css)!)

"one" --> is red and
"two" --> is green

What I want is:
On Mouse over "one" it should turn into green and at the same time "two" should turn into "red".
(On Mouse Over they should switch their colour!)

How can I get this effect!

thanks for answeres!