Once it's popped open, your cootie catcher will look like Picture 10.

现在把东南西北这样对折，打开上的小正形。

The shape of cross-section is an ellipse folded in half through one symmetry axis, and the axis keeps perpendicular with pinacoid-view.

断形状为沿对称对折的椭圆，此对称垂直截，向与平图上的流道中线无关。