Parts of Speech

A part of speech is a term used in traditional grammar for one of the nine main categories into which words are classified according to their functions in sentences, such as nouns or verbs. Also known as word classes, these are the building blocks of grammar.
Every sentence you write or speak in English includes words that fall into some of the nine parts of speech. These include nouns, pronouns, verbs, adjectives, adverbs, prepositions, conjunctions, articles/determiners, and interjections. (Some sources include only eight parts of speech and leave interjections in their own category.)
Learning the names of the parts of speech probably won’t make you witty, healthy, wealthy, or wise. In fact, learning just the names of the parts of speech won’t even make you a better writer. However, you will gain a basic understanding of sentence structure and the English language by familiarizing yourself with these labels.