Neither. IS forms part of a verb.
If is not a preposition. It is a conjunction.
"Who" is a pronoun, not a preposition or a conjunction. It is used to refer to a person or people.
"since" is not a preposition. It is a conjunction.
"for" can function as both a preposition and a conjunction. As a preposition, it shows a relationship between a noun or pronoun and other words in a sentence. As a conjunction, it connects words, phrases, or clauses.
Of is a preposition.
"Below" is not a conjunction; it is typically used as a preposition to indicate a lower position or place.
When can you use than as a preposition rather than a conjunction?
Despite is a preposition.
No, "because" is a conjunction, not a preposition. It is used to introduce a reason or explanation for something.
No, "though" is not a preposition. It is commonly used as a subordinating conjunction or an adverb in sentences.
No, the word "if" is not a preposition. It is a conjunction that is used to introduce a conditional clause.
No, "so" is not a preposition. "So" can function as an adverb, conjunction, or pronoun in a sentence, but it is not a preposition.