pronoun, particle, punctuation, verb, noun · demonstrative pronoun used to refer to a person or thing that is distant or already mentioned in the discourse.

你看那个穿红色衣服的人是谁？

pronoun · that one or that thing, as opposed to this

我不想要这个，我想要那个。

pronoun · a speech filler used when one is hesitating or thinking of what to say next, similar to "um" or "err"

那个，请问去火车站怎么走？

pronoun · used before a verb or adjective for emphasis or intensification

他那个高兴就别提了，嘴都合不拢了。

pronoun · used to indirectly refer to embarrassing or taboo topics such as sex or menstruation, or as a placeholder for a forgotten word

她那个来了，所以今天不能去游泳。