I got a sample.swf file...

i want to edit and remove some parts of sample.swf...Is this possible using flash?.

Or do we need swf source file to do this?.

i am new to flash.

You can't edit an SWF. You need the authoring file - the FLA.

Well, if it's a simple animation or .swf video--not a complicated widget or
website--you might be able to edit it.

Here's how. You convert the .swf into a .mov or a .flv, then you do your
editing in QuickTime Pro and/or the Flash encoder (Flash 8 and Flash CS3). Then
you can put it back into Flash.

But wait a minute--how do you convert a .swf into .mov or .flv? Either with
some third-party program or by loading the .swf into a new Flash CS3 file and
using File>Export to make a QuickTime .mov file, which you can then edit.