How to draw axisymmetric window grilles?

1. First, fold the paper in half and draw half of the figure you want to cut on the paper. Note that the graphics must be symmetrical in the center, and the axis is drawn on the side of the folded paper that has no open edge.

2. Secondly, after drawing the line, you can mark some areas that need to be cut off with a pen and use shadows to express them.

3. Finally, draw the axisymmetric window grilles.