Parallel lines extend indefinitely without focus, or prove to be 180 degrees. There are two kinds of vertical lines, the same plane and different planes. The same plane is 90 degrees, and different planes have one more step of translation. The line-plane parallel line is parallel to a line in the plane, and the line-plane vertical line is perpendicular to the two intersecting lines in the plane. Plane parallelism proves that two intersecting lines on one side are parallel to the other. The perpendicularity of face to face proves that the normal of one side is parallel to the other. What you say about judgment and reasoning is basically derived from the most basic, that is, two intersecting lines determine a plane or something, just do more questions.

Satisfied, please adopt.