Here are some common classes of words:
* Nouns: Words that name people, places, things, or ideas (e.g., dog, city, table, happiness).
* Verbs: Words that describe actions, states, or occurrences (e.g., run, sleep, exist, become).
* Adjectives: Words that describe nouns (e.g., big, red, happy, interesting).
* Adverbs: Words that modify verbs, adjectives, or other adverbs (e.g., quickly, very, slowly, always).
* Pronouns: Words that replace nouns (e.g., he, she, it, they, we).
* Prepositions: Words that show the relationship between a noun or pronoun and another word in the sentence (e.g., on, in, at, to, from).
* Conjunctions: Words that connect words, phrases, or clauses (e.g., and, but, or, so).
* Determiners: Words that specify the noun they modify (e.g., the, a, an, this, that).
How structural linguistics uses classes of words:
* Identifying patterns: Analyzing the classes of words in a language helps linguists identify patterns in how words are used and how they function in a sentence.
* Understanding grammar: Understanding word classes is crucial for comprehending the grammatical rules of a language.
* Developing language models: These classes are used in computational linguistics to build language models and understand natural language processing.
Important Note: The specific word classes and their definitions can vary across different languages.
It's essential to remember that structural linguistics focuses on the formal relationships between words, not their meaning. For example, "run" and "sleep" are both verbs, even though they have very different meanings.