What is the part of speech known as that shows relations with other words?

The part of speech that shows relations with other words is called a preposition.

Here's why:

* Prepositions connect nouns or pronouns (called the object of the preposition) to other words in a sentence, showing relationships of time, place, direction, or manner.

Examples:

* On the table (shows location)

* Before the game (shows time)

* With my friends (shows accompaniment)

* Under the bridge (shows position)

Let me know if you'd like more examples or explanations!