① Make an equilateral triangle ABP with AB as the side, and then draw the circumscribed circle of the triangle ABP, and the arc coincident with the square is all points P. 。
(2) Similar to the method in (1), make an equilateral triangle ABE and an equilateral triangle CDF into rectangles with AB and CD as sides respectively, then make the circumscribed circles of these two equilateral triangles into rectangles, and then make the diagonal AC (or BD) of the rectangle intersect with these two circles at points P and P' respectively. This is the demand.