answer: Mary has difficulty in getting a book which is used in Prof. Lee's course. Jim says he can borrow a copy from his roommate.
documents: #Person1#: What's that book you just picked up, Mary?
  #Person2#: The one Prof. Lee uses inhis course.
  #Person1#: Oh, I see. You'd better have it if you want to pass that course.
  #Person2#: But it costs $30. I simply can't afford it.
  #Person1#: Did you check the used book section here? Maybe they have it.
  #Person2#: No, they don't. I asked.
  #Person1#: Why don't you get it from the library?
  #Person2#: I've been trying for months, and it's always out. There are over 50 students in the course, and every single one wants the book.
  #Person1#: Listen, you know my room-mate Henry, don't you? He took the same course last year, and I remember he owns a copy. Ican borrow it from him for you.
  #Person2#: Oh, that'll be great! Thank you, Jim!