They used Euclid's algorithm to find the greatest common divisor.

Please teach me how to find the greatest common divisor.

The history of the British Empire occupies a particularly important part in world history.

Abstract algebra is a branch of mathematics that studies algebraic structures.

The Paleolithic is the first era of human history.

My grandfather was born in the 1900's.

Abstract algebra is a field of mathematics that studies algebraic structures in an abstract way.

I am studying Modern English.

The Cultural Revolution is a part of China's history.

The Third International was a historically important organization.