Unload Levels

Hi
I’m trying to unload some movies in level 10, 11, 14 and load another in level 2.
The movie in level 2 load but he level 10 and 11 are not unloading.
I’m using this script:
on (release) {
unloadMovieNum(10);
unloadMovieNum(11);
unloadMovieNum(14);
loadMovieNum(“MovieClip.swf”, 2);
}
Is there a way to write a script that say something like:
on release make sure that levels 10, 11 & 14 are unload then load MovieClip.swf in level 2?
Thanks
Alex