If you look at a Literary Chinese text, you'll almost certainly see the character "之" (zhī) all over the place. This character has four main functions in the classical language.
1. As a particle to mark modifiers
This if just a fancy way of saying that "之" is a possessive particle. If you're familiar with modern Mandarin, then you can understand the literary "之" in exactly the same way as the modern "的" (de). Remembering the key rule of "what precedes modifies what follows", have a look at these examples:
• 孔子之道 (kǒng zǐ zhī dào) [confucius – 's – way]. Here, 之 is acting like apostrophes in English: "Confucius' Way", or "The Way of Confucius".
• 明教之猶 (míng jiào zhī yóu) [understand – education – 's – strategy/path]. Again "之" works like "of" in English with the positions reversed: "The overall aim of understanding education".
2. As a direct object pronoun
The second most common use of "之" in Literary Chinese is as a generic direct object pronoun, i.e. things like "it", "him", "her" and "them" in English.
• 食之 (shí zhī) [eat – it]. This is a straightforward verb plus pronoun construction. As Weird Al said, "Eat it".
• 学而时习之 (xué ér shí xí zhī) [study – and – timely – familiar – it]. Here 之is the object of the sentence, taking the action of the verb: "To study and in time master it".
3. As a demonstrative pronoun
This is almost the same as function #2: 之 can express meanings like "this", "these" and "those".
• 食之 (shí zhī) [eat – this]. We can actually re-use this example, as it's a bit ambiguous. It could also mean "Eat this".
• 之国之王 (zhī guó zhī wáng) [this – country – 's – king]. Two examples in one! Here, the first "之" is a demonstrative pronoun, and the second is a particle. The phrase reads "The king of this country".
4. As a verb meaning "go to"
A slightly more unusual use of 之 is as a verb. It always means to go to a location or arrive somewhere; it can't express "to leave" or "going away".
• 之国见王 (zhī guó jiàn wáng) [go to – capital – see – king]. This phrase could be translated as "to go to the capital to see the king".