She is learning the grammar of the present progressive form.

When you listen to the old tales, you can imagine the lives of people in the past.

She is conducting research on the world's oldest profession.

Old World monkeys primarily inhabit Africa and Asia.

The World Trade Organization is an important organization that sets the rules for international trade.

The World Health Organization is working to improve public health worldwide.

New World monkeys live in South America.

The World Health Organization is working to improve public health worldwide.

This photo has a shallow depth of field, so the background is blurry.

World War I was a large-scale war that lasted from 1914 to 1918.