A.Because some book in the library are very expensive. B.Because some books in the library are rare. C.Because sometimes students need certain materials urgently. D.Because some students won't return the books they borrow.
【简答题】Last summer, Jeff became a middle school student. He was a good student, and he always worked hard. He had a test in the first month and he finished the questions easily until he read the last one:” 小...