You can use Flash's "Motion Tweening" feature to make animations easily.
The "Tweening" feature helps you create animations without having to draw each of the frames yourself.
Try a simple example with a bouncing ball:
First, in a new Flash document, use the Oval tool to create an oval (circle) at the top of the Stage.

Next, indicate the last frame of the animation by clicking on frame 10 in the Timeline and selecting <Insert > Timeline > Keyframe>.

Then, highlight frames 1 through 10 and select <Insert > Timeline > Create Motion Tween>.