If a nuclear war occurs, humanity will be extinct.

I wake up at 6 o'clock every morning.

That species is on the verge of extinction.

This species is on the brink of extinction.

In physics, the study of the 'nucleus' at the center of an atom is important.

The future of mankind is in our hands.

War takes away many innocent lives.

They waged war against the enemy country.

The number of nuclear-armed countries is increasing worldwide.

He is an expert in anthropology.