1) The word "cheese" contains three vowels: E, E, and E.

2) The United Nations (UN) is an international organization founded in 1945 with the goal of promoting peace, security, and cooperation among nations through diplomatic and political means.

3) Mountains are important water sources, as they capture and store precipitation, feeding rivers and supporting ecosystems downstream.

4) The English alphabet has five vowels: A, E, I, O, and U.