No, ‘was’ is not a preposition. It is a verb, specifically the past tense of the verb ‘to be.’
In English, prepositions are words that show the relationship between nouns or pronouns and other words in a sentence. Examples of prepositions include ‘in,’ ‘on,’ ‘at,’ ‘between,’ and ‘under.’ However, ‘was’ functions as a linking verb, connecting the subject of a sentence to a subject complement that provides more information about the subject.
For instance, in the sentence ‘She was happy,’ ‘was’ links the subject ‘She’ to the adjective ‘happy,’ describing her state. Therefore, understanding the role of ‘was’ as a verb rather than a preposition is crucial in grammar.