Phonemes

units of sound 

Morphemes

units of sound that contain meaning

Words

morphemes that can stand by themselves in meaning

Phrase

A word or a group of words that create(s) a single unit of meaning. 

Clause

A grammatical unit that contains a subject and a verb.

Sentence

A clause or a group of clauses that create a complete expression of thought.

For more information on syntax:

Click here for the creation of sentences.

Click here for the structure of sentences.