Japan's net national product is an important indicator of the health of the economy.

This factory strictly controls the emission of hydrogen sulphide.

The troposphere is the lowest part of the Earth's atmosphere, and most of the weather occurs here.

Carina is one of the constellations in the southern hemisphere.

He is collecting stamps.

The police detained him in the detention center.

He stood up and started talking.

He decided to study abroad in America.

He is an international student from America.

He is a first-class chef.