Adpositions are a closed class. They can be used in three different ways.
As a Preposition
The most basic use for an adposition is prefixed to a noun to signify where the action is taking place with relation to a reference. These act as prefixes.
Their nature as a prefix continues to apply even when the noun is already case-marked
As a Nominal or Verbal Modifier
Adpositions can be used to form compound nouns:
and compound verbs:
As an Adverb
Adpositions can be used independently to show the position of the action relative to the speaker, or the direction in which the action proceeds. Unlike other adverbs, these are placed before or instead of the auxiliary.
The auxiliary must appear to support an adverbial adposition in copular clauses.
This list includes both relative and absolute terms.
These can be used to refer to locations in either space or time.
These can only be used to refer to locations in space.
These refer to motion.
This group have animate objects.
This group have inanimate objects.