The parts of speech explain how a word is used in a sentence. Therefore, let´s say that Parts of speech is one of the classes, group or category of words into which those words are divided according to their grammar structure. There are eight main parts of speech (also known as word classes) such as : nouns, pronouns, adjectives, verbs, adverbs, prepositions, conjunctions and interjections. It's quite important to recognize parts of speech. This helps you to analyze sentences and understand them. It also helps you to construct well-structured sentences. Now, let´s define eight of the parts of speech: 1. Noun : This part of a speech refers to words that are used to name people, animals, places, things, or feeling/qualities/ideas, or events. Nouns are often used with an article ( the , a , an ), but not always. Proper nouns always start with a capital letter; common nouns do not. Nouns can be singular or plural, concrete or abstract. Types of nouns.