1.ASA: sandwiched by two corners; AAS: (arbitrary) one side of two corners (not clamped);

2.ASA means there are two corners, and that s is the side sandwiched between the two corners. AAS means that there are two corners, and that s is not the side they share.

3.AAS refers to the opposite side of two corners and one corner, and ASA refers to two corners and their sides.

4.ASA is the two corners next to the edge, that is, the corner clip edge; AAS is an edge, the diagonal of this edge, and the adjacent angle of this edge.

5. One is the corner edge and the other is the corner edge. It's just that the positions of the sides are different, and they are all composed of two corners and one side.

The edge of the first theorem cannot be sandwiched between two angles;

The two corners of the second theorem must be adjacent to this side (this side must be in the middle of the two corners).

6. If there are two triangles, two of which have equal diagonals and a pair of sides, then the two triangles must be congruent. If the two corners are sandwiched, ASA is not sandwiched, AAS.

7.ASA is an angle, that is, two angles sandwich an edge, and AAS is an angle, that is, two adjacent angles add an edge, and one of them corresponds to that edge.