"That soldier drinks tea."
Translation:O asker çay içer.
O also means "that" or "those", so you could put "O, çay içer." to mean "He drinks tea." and the comma is so you know that it is not "That tea" which of course would not make sense as "That tea drinks."
Scroll past the English to Turkish to get to the Turkish to English: http://www.turkishdictionary.net/?word=o