Final answer:
The phrase 'Susan left her lunch at home' is a complete sentence because it has a subject and a verb and expresses a complete thought. Sentence fragments lack one of these elements and do not represent a complete thought.
Step-by-step explanation:
The question, 'susan left her lunch at home sentence. or fragment,' can be answered by examining the structure of the phrase provided. This phrase is a complete sentence because it has a subject ('Susan') and a verb ('left'), expressing a complete thought about Susan leaving her lunch at home. A sentence fragment, on the other hand, would be missing a subject, a verb, or not express a complete thought, making the phrase unclear or incomplete.
In contrast to a fragment, a complete sentence provides enough information to stand alone. For example, 'The lunch was delicious' and 'She had bread set' are both examples of complete sentences. Each includes a subject performing an action or being described in a way that conveys a complete thought.