To reshape a line or shape outline, drag any point on a line using the Selection tool. The pointer changes to indicate what type of reshaping it can perform on the line or fill.
Flash adjusts the curve of the line segment to accommodate the new position of the moved point. If the repositioned point is an end point, lengthen or shorten the line. If the repositioned point is a corner, the line segments forming the corner remain straight as they become longer or shorter.

Some brush stroke areas are easier to reshape if you view them as outlines.
If you are having trouble reshaping a complex line, smooth it to remove some of its details, making reshaping easier. Increasing the magnification can also make reshaping easier and more accurate.
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To reshape the segment, drag from any point.
To drag a line to create a new corner point, control-click (Windows) or Option-click (Macintosh).