Action script flash 8.2

1

In flash 8.1 this code works fine,
but in 8.2 it says:

layer=Layer 1, frame=1:Line 3: Syntax error.
Xmin = refrect:_x;

Numstars = 100;
Numlevels = 6;
Xmin = refrect:_x;
ymin = refrect:_y;
Xmax = refrect:_width;
Ymax = refrect:_height;
t = 1;
while (Number(t)<Number(numstars)) {
duplicateMovieClip(“star”, t, t);
xspeed = int((t/numstars)numlevels);
setProperty(t, _x, Number(random(xmax))+Number(xmin));
setProperty(t, _y, Number(random(ymax))+Number(ymin));
setProperty(t, _xscale, xspeed20);
setProperty(t, _yscale, xspeed*20);
tellTarget (t) {
xspeed = xspeed;
}
t = Number(t)+1;
}
setProperty(“star”, _visible, 0);
setProperty(“refrect”, _visible, 0);