What are the three steps to make shape tween animation?

1. Create a blank keyframe on the timeline panel or select the keyframe where the animation starts to play, and draw a graph. In general, it is best to use one object in one frame.

2. Create or select a key frame at the end of the animation and draw another graph.

3. Click the start frame, click the small triangle next to Tween on the Properties panel, and then select Shape from the pop-up menu. At this point, you can see that the timeline has changed-light green background and arrows, and a shape tween has been created.

If the dotted line appears, check whether there are non-vector diagrams or other elements on the two key frames before and after, and delete them.