Congruent triangles refers to two congruent triangles whose three sides and three angles correspond to each other. Congruent triangles is a kind of congruence in geometry. According to congruence transformation, two congruent triangles can be translated, rotated, axisymmetrical or overlapped. Two triangles are congruent triangles when their corresponding sides and angles are completely opposite. Usually, when verifying two congruent triangles, three equal parts are used to verify, and finally the result can be obtained.