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.

He believes that 'money is everything in this world.'

He did aerial photography using a drone.

I burned trash in the yard today.