How to transition with AS?

1

I have so far figured out how to use AS to change and resize the information presented to a user based on simple mouse inputs. The following does what I want it to, only too abruptly. How can I transition (zoom) the resizes in this script, which I’ve highlighted in blue?

[color=Blue]on (rollOver) {
_height = 360;
_width = 360;
_x = 407.8;
_y = 245.9;[/color]

 gotoAndPlay("Design");
 _root.mc_erTitles._alpha = 0;
 _root.mc_erText._alpha = 0;

}
on (release) {
tellTarget (_root.mc_erTitles) {
gotoAndPlay(“titleDesign”);
gotoAndPlay(“Design”);
_root.mc_erTitles._alpha = 70;
_root.mc_erText._alpha = 100;
}
tellTarget (_root.mc_erText) {
gotoAndPlay(“text_design”);
}
[color=Blue] _height = 158;
_width = 158;
_x = 308.8;
_y = 146.4;[/color]
;
}