Hello, Dr. Green.

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In this expression, is Dr. Green a doctor who works at a hospital? Or is Dr. Green a professor in college?

He could be either one, depending on the context.

Do you have this sentence in a whole paragraph?

what is the subject and what is the predicate, of the following sentence.

The driver of the pickup truck backed into my car and then sped away.

To determine whether Dr. Green is a doctor who works at a hospital or a professor in college, we need more context. Without additional information, it is not possible to accurately determine the profession of Dr. Green. To find out more, you can do the following:

1. Ask for clarification: If you have direct contact with the person who referred to Dr. Green, you can inquire about their profession.

2. Research online: Look for information about Dr. Green on the internet. Search for their name along with relevant keywords such as the name of the hospital or college they are affiliated with. This can help you find their background or any relevant professional information.

3. Check professional directories: Look for directories specific to doctors or professors and see if Dr. Green is listed. These directories often include contact information and professional affiliations.

Remember that Dr. Green may not necessarily be a doctor or professor, as the title "Dr." can also be used by individuals with doctoral degrees in various fields.