He wrote a poem using the four treasures of the study.

An arc discharge occurs when electricity passes through the air.

Trigonometry is a branch of mathematics that studies the relationship between angles and triangles.

In his study of international law, he particularly focuses on jus gentium.

Phoenix is one of the constellations in the southern hemisphere.

When he opened the supernatural box, an astonishing power was released.

You can use spectroscopy to examine the components of a substance.

In the old days, people used to consider milk as an important source of nutrition.

Our opinions differ.

The content of this book is very high quality.