Teacher: In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Teacher: Now, understand the problem? If you are still confused, see the following example:
Passage: Nearing London, Oliver encounters Jack Dawkins, a pickpocket more commonly known by the nickname the "Artful Dodger", and his sidekick, a boy of a humorous nature named Charley Bates, but Oliver's innocent and trusting nature fails to see any dishonesty in their actions. The Dodger provides Oliver with a free meal and tells him of a gentleman in London who will "give him lodgings for nothing, and never ask for change". Grateful for the unexpected assistance, Oliver follows the Dodger to the "old gentleman's" residence. In this way Oliver unwittingly falls in with an infamous Jewish criminal known as Fagin, the gentleman of whom the Artful Dodger spoke. Ensnared, Oliver lives with Fagin and his gang of juvenile pickpockets in their lair at Saffron Hill for some time, unaware of their criminal occupations. He believes they make wallets and handkerchiefs.
Solution: Who believes Fagin's gang make wallets and handkerchiefs?.
Reason: This question is based on the following sentence in the passage "He believes they make wallets and handkerchiefs". It evaluates the understanding that the pronoun "he" refers to name "Oliver". You can ask questions like this one about most pronouns in a paragraph.

Now, solve this instance: Passage: Don McKay is a lonely high school janitor who one day receives a letter from his high school sweetheart, Sonny. In it, she asks him to come visit her back in their home town, because she is dying of an unnamed disease. At first he is reluctant because he had been a suspect in a murder case there years before, but Don decides to go. He arrives and gets a ride to Sonny's house by an eccentric cab driver named Samuel.
Don meets Sonny, as well as her strange caregiver Marie. Marie's coldness towards Don makes it clear that she doesn't approve of his presence. Don spends the night, and he and Sonny make love. The next morning, Sonny's Doctor, Lance Pryce visits. While Marie and Sonny are out, Pryce attacks Don, and after a struggle, Don kills the man, and hides the body in a bed of leaves behind the garden. However, Don had just suffered an allergic reaction to a bee sting, and blacks out shortly after hiding the body. He awakens in the hospital, where Sonny proposes marriage and claims that she had recently spoken to Pryce. 
Don goes to see his old friend Otis, and tells him what happened. Otis agrees to help Don get rid of the body that night, but when he arrives it has vanished. Sonny rushes out, thinking the men are burglars, and Otis runs off. After an argument, Don returns home for a few days, eventually getting another letter from Sonny asking him to come back to her.
Student:
What are the professions of the people the janitor meets at Sonny's house?