search for: aerea

Dear R users, I hope that this question is not too dumb, but I can't figure out how to do it. I plot a function, e.g. plot(sin, -pi, 2*pi). Then I would like to have the aerea from the x-axis up to the graph from x ranging from -3 to 0, shaded red and the other part (x from 0 to 6) under the graph e.g. green or sth. like that.. Any hints on how to do that? I could draw lines (different line-styles), but can't I simply fill these two aereas in e.g. different colors?...