(1) connects AN and DM respectively, which is proved by the property that the median line on the hypotenuse of a right triangle is equal to half of the hypotenuse;

(2) respectively connecting AN and DM; Take the midpoint f of AB and connect FP and FN respectively; Take the midpoint g of BD and connect GM and GP respectively.

Using the theorem of triangle midline and the property that the midline on the hypotenuse of a right triangle is equal to half of the hypotenuse, it is proved that △ FPN △ GMP.