Why are North South East and West not prepositions?

Answer 1

Any of the compass directions, such as north, can be a noun, an adjective, or an adverb depending on how it is used. Example of noun: Look to the north. The article adjective "the" signals that a noun is coming. Example of adjective: Moss usually grows on the north side of the tree. The word "north" modifies the word "side," which is a noun, so "north" must be an adjective. Example of adverb: The bird was flying north. The word "flying" is a verb and "north" modifies the verb, so "north" must be an adverb in this sentence.

Now to get back to your original question of why the directions are not prepositions. According to dictionary.com, a preposition is "any member of a class of words found in many languages that are used before nouns, pronouns, or other substantives to form phrases functioning as modifiers of verbs, nouns, or adjectives, and that typically express a spatial, temporal, or other relationship, as in, on, by, to, since." For example: He walked up the staircase. In this case "up" is a preposition of the prepositional phrase "up the staircase.". Now look at this example: The boy looked up. Now "up" is no longer a preposition because there is no prepositional phrase, so it is just an adverb modifying the verb "looked." In the case of compass directions, we say things like, "He looked north of the house." Here, "of" is the preposition, not "north."

Answer 2

North, South, East, and West are not considered prepositions because they do not show the relationship between nouns and pronouns in a sentence. Instead, they are direction words or adverbs that indicate location or movement. Prepositions typically describe the relationship between objects or individuals in a sentence.