tetrahedron

And so now I have hydrogens at the four corners of a tetrahedron.

放在碳正四面体,的四个角上。

So, this forms a tetrahedron, which forms the sp3 hybrid orbitals.

这就形成了一个四面体，它是由sp3杂化轨道形成的。

The shape of a water molecule is such that each H2O molecule is surrounded by four neighbours arranged in the shape of a triangular pyramid - better known as a tetrahedron.

一个水分子的形状是这样的：相邻地四个水分子组成一个金字塔形的四面体。