He is an expert in algebraic geometry and has written many papers in the field.

Riemannian geometry is a field of mathematics that studies geometric objects such as curves and surfaces.

He excels in understanding intuitive geometry.

He got the highest grade in the demonstrative geometry class.

He is immersed in the study of geometrical optics.

In this right triangle, since one angle is 30 degrees, its complementary angle is 60 degrees.

The opposite angles of a quadrangle intersect each other.

The wildebeest is a very rare animal.

Mr. Kakuma is my best friend.

Anyway, we need to contact her.