1. By Skill:
* Speaking: The ability to produce sounds to communicate.
* Listening: The ability to understand spoken language.
* Reading: The ability to comprehend written language.
* Writing: The ability to express thoughts and ideas in written form.
2. By Linguistic Level:
* Phonology: The study of sounds in language.
* Morphology: The study of word formation and structure.
* Syntax: The study of sentence structure.
* Semantics: The study of meaning in language.
3. By Language Type:
* Spoken Language: The primary form of language, using spoken sounds.
* Written Language: A visual representation of spoken language using symbols.
* Signed Language: A visual language using hand gestures and facial expressions.
* Body Language: Non-verbal communication using body movements, gestures, and facial expressions.
4. By Language Function:
* Pragmatics: The study of how language is used in social contexts.
* Discourse Analysis: The study of language in extended texts and conversations.
* Psycholinguistics: The study of how language is processed and understood by the brain.
* Sociolinguistics: The study of the relationship between language and society.
It's important to note that these categories are interconnected and not mutually exclusive. For example, speaking involves phonology, morphology, and syntax.
Ultimately, the "four areas of language" will depend on the specific context and purpose of the discussion.