under the Mask layer. When you lock the Mask layer and the affected layers, you can see the effects of the mask on the screen. 1. Select the Incoming Text Message layer, and then press Shift and select the Low Batt layer to select all the layers in between. 2. Drag the layers on top of the Mask layer name; the mask icon darkens when the layers are positioned correctly. When you release the mouse, all the selected layers are indented beneath the Mask layer. 3. Lock the Mask layer, and all the indented layers. 4. Scrub the Timeline to preview the animated text. [View full size image]   Using Tweens to Simulate a Shaking Motion After the low battery message, the cellphone shakes. You'll create that shaking motion using motion tweens and rotation settings. 1. Unlock the Cellphone layer. 2. Select frame 228 in the Cellphone layer, and press F6 to insert a keyframe. 3. Select frame 238, and press F6 to insert a keyframe. 4. With frame 238 selected, select the phone graphic on the Stage. 5. In the Transform panel, type -18 in the Rotate box, press Enter or Return, and then use the Selection tool to move the phone under the table. Note You may need to change the view to see the entire Stage. You can use the View pop-up menu above the Stage, or use the Zoom tool in Reduce mode. 6. Select any frame between frames 228 and 238. In the Property inspector, select Motion from the Tween menu. 7. Select frame 230, press F6 to insert a keyframe, and then select the cellphone graphic on the Stage. 8. In the Transform panel, type -18 in the Rotate box, and press Enter or Return to apply it. Use the Selection tool to shift the phone to the left. 9. Select frame 232, press F6, and select the phone graphic. 10. Type 42 in the Rotate box, and press Enter or Return. 11. Shift the phone to the right until it is almost to the right edge of the background. [View full size image] 12. Select frame 234, press F6, and select the phone graphic. 13. Type -18 in the Rotate box, and press Enter or Return. 14. Shift the phone to the left so that it is in a similar position as on frame 230. 15.