1, there is only one straight line between two points.

2. The line segment between two points is the shortest.

3. The complementary angles of the same angle or equal angle are equal.

4. The complementary angles of the same angle or equal angle are equal.

5. There is one and only one straight line perpendicular to the known straight line.

6. Of all the line segments connecting a point outside the straight line with points on the straight line, the vertical line segment is the shortest.

7. The parallel axiom passes through a point outside the straight line, and there is only one straight line parallel to this straight line.

8. If two straight lines are parallel to the third straight line, the two straight lines are also parallel to each other.

Axiom refers to the basic proposition that is based on the self-evident basic facts of human reason and has been tested by human practice for a long time without further proof.

In mathematics, the word axiom is used in two related but different meanings-logical axiom and illogical axiom. In both senses, axioms are the starting point for deducing other propositions. Unlike theorems, an axiom (unless it is redundant) cannot be derived from other axioms, otherwise it is not the starting point itself, but some kind of result that can be obtained from the starting point-it can be simply classified as a theorem.