<p>Normally when you trim regions by dragging with the mouse, it affects only the selected regions. Their lengths are directly affected by the trim operation, but nothing else is. Sometimes though, you'd like to trim a region that directly adjoins another, and keep this relationship the same - you're not trying to make one of the regions extend over the other - you'd like the junction to move in one direction or the other as part of the trim. This requires trimming both regions on either side of the junction, in opposite directions. <em>Push/Pull</em> trim, activated by pressing shift key before starting the drag, will do just that. Here's a few pictures to show the difference in the results of a normal trim and push/pull trim. First, the initial situation:</p>
<p>There is no overlap, and the end of the earlier region has been moved along with the start of the later region, so that they still directly adjoin each other.</p>
