1.
diagonal point of a complete quadrangle
完全四角形的对边点
2.
A plane figure with four sides and four angles.
四边形有四个边和四个角的平面图形
3.
diagonal line of a complete quadrilateral
完全四边形的对角线
4.
A four - sided plane figure with four right angles.
矩形，长方形具有四个边的方形，有四个直角
5.
B： Yes, it is. A rectangle has four sides and four corners.
是的。长方形有四条边和四个角。
6.
a parallelogram with four right angles.
有四个直角的平行四边形。
7.
a tetrahedron with four equilateral triangular faces.
有四个等边三角形面的四面体。
8.
Having four sides and four angles;square or rectangular.
四边形的带有四条边或四个角的；长方形或正方形的
9.
Put four small triangles under the big rectangle.
把四个小三角形放在大长方形的下面。
10.
A square is a figure with four equal sides and four right angles.
正方形是具有四个等边和四个直角的图形。
11.
a parallelogram with four equal sides; an oblique-angled equilateral parallelogram.
四个边相等的平行四边形；不是直角的等边平行四边形。
12.
The Application of “Four Centers” of a Triangle in Triangular Cone;
三角形的“四心”在三棱锥中的应用
13.
A plane figure consisting of four points, no three of which are collinear, connected by straight lines.
四边形，四角形由四个角组成的平面图形，没有任何三个点共线，通过直线相连接
14.
Reasons behind the Four Grades of People in Yuan Dynasty;
多角度解读元代四等人制形成的原因
15.
The base of the triangle coincides with one side of the square.
这三角形的底边与这四边形的一边相重合。
16.
A Shape Optimization Research for Quadrilateral Mesh over the Triangular Surface;
三角网格曲面上四边形分割的形状优化研究
17.
Study on the Triangle Mesh Translate into Quadrangle;
关于三角形网格转化为四边形网格的研究
18.
(geometry) a plane rectangle with four equal sides and four right angles; a four-sided regular polygon.
（几何）有四个相等的边和四个直角的平面长方形；有四个边的等边多角形。