All the words you say or write, read or hear are one of the 9 parts of speech*. It is helpful to know the names of the parts of speech (also known as word classes), and to be able to identify the words you meet and use as one of those parts of speech. If you don't, you will not be able to understand some of the grammar explanations you read or that your teacher gives you. For example, if you don't know what a verb is, you will not understand when you teacher says: "This sentence is incorrect; it doesn't have a verb."
Here is a table of the 9 word classes or parts of speech:
|Part of speech||Most common function||Examples|
|noun||to name a person, place, or thing||teacher, mountain, idea|
|verb||to do or be something||eat, sleep, think, seem|
|adjective||to describe a noun||silly, huge, boring|
|adverb||to describe how something is done||quickly, well, carelessly|
|pronoun||to take the place of a noun||I, she, it, that, them|
|conjunction||to join words, phrases, and clauses||and, so, because, when|
|preposition||to introduce a phrase of when, where or how||on, in front of, by, with|
|article*||to specify or generalize a noun||the, a, an|
|interjection||to express emotion||hey, wow, ouch|
For advanced learners and teachers: The word classification presented on this page is highly simplified and follows the traditional method of categorizing words by their meaning; for example, a noun is the name of a person, place or thing. Modern linguistics has abandoned such a naive approach, and uses criteria such as form and function (or distributional property) in deciding on the classification of any given word. Hence a noun would be described as a word that has certain derivational or inflectional characteristics (form) or certain syntactical abilities, such as acting as the subject or object of a clause (function). Indeed, the very term part of speech is deprecated in favour of word class or form class.
The intention of this page, however, is not to present a reliable set of criteria for categorizing words, but simply to introduce to English language learners one part of the essential metalanguage they will need to know in order to make sense of their dictionaries, grammar books and language instruction.
*In the modern approach, the three article words are typically subsumed in a word classes called determiners or determinatives. Some modern grammarians group pronouns as a sub-set of nouns and not as a separate word class. In fact, there is currently no unanimity on the correct designation of a significant proportion of English vocabulary.