that person
In English, when we talk about a noun, we say:
the person
the colleague
the place
In mandarin, we cannot just to say "the", we have to make it more specific, need to use "this" or "that" instead of "the". It's depends on where the noun is. For example:
If a person or a place just in front of you, you say "this person" or "this place".
If the person or a place is far from where you are, you say "that person" or "that place"