Besides Europe, what other areas were battlegrounds during World War I?

The World War I (WWI), known as well as the First World War, the Great War or the war to end all wars, took place from July 28th, 1914 to November 11th, 1918. As a direct result of this world conflict approximately nine (9) million soldiers and seven (7) million civilians died, deaths which were intensified by new industrial and technological developments.

Although WWI was originated in Europe, other areas besides Europe were also battlegrounds during it, for instance, Africa, the Pacific Islands, China, the Middle East, Indian Ocean, and off the coast of South and North America.