Language has five primary properties:

• Communicative: The purpose of language is to communicate information.
• Symbolic: Words are merely arbitrary symbols that denote concepts in the world.
• Structured: Language has structure on many different levels such that the tokens at a particular level can only be combined according to certain rules.
• Productive: The rules of language are such that there are an infinite number of possible valid utterances.
• Dynamic: Language evolves to meet the needs of its users.

Phonemes:

The most basic unit of a language is its phonemes. Phonemes are the individual sounds that are used in a language.

Morphemes:

Phonemes get combined into morphemes, which are the smallest meaning-carrying units of a language.

Morphemes are either root words, such as "run" or "chair," or affixes, such as "-s,"

"-ing", or "pre-"

Morphemes that convey actual meaning are called content morphemes. These are things like "-ing" or "run"

Morphemes that just take up space are called function morphemes. These are words like "or", "a", "the"

The lexicon is the set of morphemes you know. Whereas there are only around 50 phonemes in English, people generally know roughly 80,000 morphemes, all of which are constructed from these 50 phonemes.

Syntax is the stuff that makes the world go round. It is the set of rules by which speakers can put words together into sentences.

The stuff we’ve been talking about the last two weeks: How do words convey meaning?
 
 

The structural level at which sentences are put together to form a comprehensive body of information that people are trying to share.

The primary question is this: Is speech somehow special? The evidence is unclear:

Evidence for speech being special:

• Processing speed: We can process up to 50 phonemes per second in our native language, but only about 2/3 of a phone per second of non-speech sounds.
• Categorical perception

• McGurk effect?

• Aphasias and anomias? Brain-damage disorders that seem to affect language but not other auditory processes.

• Phonetic refinement theory: We use top-down processes to determine what we heard, which is why speech seems special. We don’t have this extra assistance for non-speech sounds.

• Phonemic-restoration effect: Take a word and delete a phoneme. Replace the missing phoneme with a non-speech sound (such as a clang or a cough). People will swear they actually heard the missing phoneme.

The "Syntax tendency":

People appear to easily be able to parse sentences, even when the parse is ambiguous or when the sentence is nonsense.

"They are cooking apples."

People show "syntactical priming."

Speech errors generally involve the garbling of syntactically equivalent elements, and don’t usually result in ungrammatical sentences.