Identify the simple subject in the following sentence the patients at memorial medical center receive the best care possible

The subject of a sentence is the person or thing that is doing the action. Often it comes first in a sentence. A simple subject is only the person or thing. A complete subject is the person or thing that is doing the action plus any modifiers (a, an, the, and other adjectives for example)EXAMPLE: The fuzzy dog ate his dinner.The simple subject is: dogThe complete subject is: The fuzzy dog. (The and dog describe/modify dog.)
The simple subject in this question is "patients". 
The complete subject is "The patients at Memorial Medical Center".
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