ni

ni is similar to "this" and "that" and "yonder" in english. it is used in two different contexts. The easiest way to use ni is to point at a physical object. This could be demonstrated with a finger, a gesture of the head, a glance, or even a drawn arrow. In those contexts, the semantic space of "ni" is that thing you're pointing at. You can also use ni as a modifier to be more specific. Are you pointing at a specific box? You can say "poki ni." are you pointing at a specific location? "ma ni" works just as well as "ni." What about the current situation? "tenpo ni" is perfect for this!

extended into the metaphorical, ni can also be used to point at things you or others have said. It always stands in for at least one clause (a clause is any phrase with a verb in it). Most often you'll see it standing in for a previous or upcoming sentence.

ni can also be used as a modifier to elaborate on a word in a sentence. If your sentences are getting too long, ni is among the easiest way to break it up. you can turn "mi wile e soweli pi linja pi suwi mute" into "mi wile e soweli ni: linja ona li suwi mute." Note how "ona" in the next sentence stands in for "soweli ni." If you want to learn more about this, look into anaphora and deixis.

toki pona lacks proximity distinctions, unlike english. In english, the difference between "this" and "that" and "yonder" is how close the object is to the speaker and listener. toki pona's "ni" can fill the meaning of any of these. It is more general, but you can usually tell what it's talking about due to context. If you're worried that people might not be able to tell where something is, you can say how close it is by using "poka" and "weka," among other tools.