Fireworksmx taught you to make corner rectangles.

1. Create a new file with a width of 150 pixels and a height of 100 pixels, with any background color.

2. Select the Rectangle tool in the tool panel and draw a rectangle in the editing area.

3. Select the tool panel's "knife Tool" in the vector section, and hold down the SHIFT key to cut the border of the upper-right corner of the rectangle.

4. After cutting the picture:

5. Click the Subselection tool in the Tools panel.

6. Select vertices.

7. Press the DEL key on the keyboard to delete.

8. Continue to turn the left corner into a missing angle. Select the Pen tool for the vector section of the tools panel.

9. In the lower left corner of the two borders equidistant each click.

10. Select the vertices in the lower-left corner using the Subselection tool.

11. Press the Del on the keyboard, delete the bottom left corner of the vertex as shown.