His victory was by a thin margin.

The United Nations Security Council plays a crucial role in maintaining world peace and security.

General relativity is a theory of physics proposed by Einstein.

Special relativity is one of the fundamental theories of physics.

This area is seriously contaminated with radioactive isotopes.

He feels dizzy when he stands up suddenly due to orthostatic hypotension.

My father was diagnosed with ankylosing spondylitis.

In organic chemistry, pyruvic acid plays an important role.

His father fell into a persistent vegetative state due to a traffic accident.

Basic oxides react with acids to produce salt and water.