In organic chemistry, pyruvic acid plays an important role.

The study of filterable pathogens is an important part of virology.

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

Special relativity is one of the fundamental theories of physics.

General relativity is a theory of physics proposed by Einstein.

The Czechoslovak Socialist Republic was once an existing country.

The People's Socialist Republic of Albania was once an existing country.

The Democratic Socialist Republic of Sri Lanka is located in South Asia.

The Socialist Federal Republic of Yugoslavia was a country that once existed.

The Soviet Socialist Republics Union was a country that once existed.