In this tutorial, I'm going to show you how to convert lines to fills in Flash using Convert Lines to Fill function. I'm also going to explain why ever do such thing. The following info will be especially useful for those of you who draw in Flash, but not only. If you're an ActionScript geek, then you will probably not find the below info that useful. :-) To convert your Line to a Fill, select it and go to Modify>Shape>Convert Lines to Fills.