For instance, if the text says that Eli Whitney invented the cotton gin, look for a test question over that. Look for bold printed text. The author of the book is emphasizing the importance of that fact. The teacher may do the same on the test. Look for a summary at the end of the chapter.
Teachers often pull test questions from summaries.
Check out any exercises in the chapter, review questions, and the like. I have known teachers to take review questions from the chapter and simply reword them for the test. Allow him to answer. If the answer is wrong, immediately give the correct answer. Do not allow the wrong answer to stay in his mind too long, as this could cause confusion later.