Not every country belongs to the U.N.

Tom and Mary participated in a model U.N. conference.

The official languages of the United Nations are Arabic, Chinese, English, French, Russian and Spanish.

Stephen O'Brien, the United Nations Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator, has said that more than 20 million people faced the threat of starvation and famine in Yemen, Somalia, South Sudan and Nigeria.