Final answer:
A phrase is a group of words that functions as a single unit within a sentence, while a clause contains a subject and a predicate and can express a complete thought.
Step-by-step explanation:
A phrase is a group of words that functions as a single unit within a sentence, but it does not contain a subject and a predicate, so it cannot express a complete thought on its own. Examples of phrases include "on the table" or "with a smile".
A clause is a group of words that contains a subject and a predicate, allowing it to express a complete thought. There are two types of clauses: independent clauses, which can stand alone as a sentence, and dependent clauses, which cannot. Examples of clauses include "I ate an apple" and "because I was hungry".
Therefore, the main difference between a phrase and a clause is that a phrase does not have a subject and a predicate, while a clause does.
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