An angle in which two angles are on the same side of the section line and two straight lines are on the same side of the section line is called.

Correspondence angle

Two parallel straight lines AB and CD are cut by the third straight line EF. If both corners are on the inside of two straight lines and on both sides of the third straight line, then such diagonal lines are called.

alternate interior angle

The two corners are on the same side of the cutting line, and between the two cutting lines, a diagonal with this positional relationship is mutual.

Continuous internal angle

The isosceles angles are equal and the two straight lines are parallel.

Internal dislocation angles are equal and two straight lines are parallel.

The internal angles on the same side are complementary and the two straight lines are parallel.

The two straight lines are parallel, with the same included angle and the same internal angle, which complement each other.