Which of these countries belonged to the central powers during world war 1?

The central powers of World War I was made up of The Austria-Hungary Empire, The Germany Empire, Ottoman Empire and the Kingdom of Bulgaria.

The Allies of World War I was made up of Russian Empire, The British Empire, The French Empire, Serbia, Empire of Japan.

And was later on joined by Italy, Portugal, Romania, United States, Greece, Brazil, Siam and China.