The doctor examined his semen sample.

It is important to learn the history of the World War.

The volume ratio of this container is 1:2.

Sekibune is a type of boat that was used for military purposes historically.

An international auxiliary language is a language used for communication beyond countries and cultures.

He is troubled by chronic headaches.

His work has a unique worldview.

Remembering the proverb 'haste makes waste', he acted carefully.

He likes to take a walk in the park at dusk.

New World monkeys live in South America.