Given that the points D, e and F are respectively the midpoint of the edges AB, BC and Ca of △ ABC, connecting de and EF, if we want to make the quadrilateral ADEF diamond, we need to add the following conditions______ Just fill in one

Given that the points D, e and F are respectively the midpoint of the edges AB, BC and Ca of △ ABC, connecting de and EF, if we want to make the quadrilateral ADEF diamond, we need to add the following conditions______ Just fill in one

From the meaning of the title, de and EF are the median line of the triangle, so the quadrilateral ADEF is a parallelogram. To make the parallelogram a diamond, just add AB = AC, when AB = AC, points D and F are the midpoint of AB and AC respectively, so AE = AF, so we can prove that the parallelogram ADEF is a diamond, and when ∠ B = ∠ C is added, we can also prove that the quadrilateral ADEF is a diamond