给儿童介绍不同种类的三角形，如等边三角形、等腰三角形、不等边三角形和直角三角形。

Introduce children to different kinds of triangles, such as equilateral, isosceles, scalene, and right.

youdao

给儿童介绍不同种类的三角形，如等边三角形、等腰三角形、不等边三角形和直角三角形。

Introduce children to different kinds of triangles, such as equilateral, isosceles, scalene, and right.

youdao