1. How do you call those people who do X-ray for you?
Do you call them X-ray doctors? What's the proper or common name to address these people?
2. I have a friend named Peter.
I have a friend, named Peter. (which one is correct? Do I need that comma, and is it in the right place?)
3. How do you use the conjunction "in which", i often see "in which" in many English sentences.
How do you use "in which" in a sentence?
Thank you very much. Deeply appreciated for your help.