It is believed that black dwarfs are formed by the cooling of white dwarfs.

She is conducting research on the world's oldest profession.

Rabbits are herbivores and mainly eat grass.

He is of the yellow race and has a deep understanding of Asian culture.

The Great Eastern Japan Earthquake is one of the most damaging earthquakes in Japanese history.

My heart was healed by the beautiful scenery of Nara.

Learning Modern English is important for smooth international communication.

He wrote a sentence using a pronoun.

My grandfather was born in the 1900's.

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