You would most likely not travel to another country without getting a lay of the land first.  Often we read a tourism book or look at a map.  We might try to learn a few words in the other language.   If the country is similar to our own (England speaks the same language as the U.S. so feels more familiar) we might do less preparation than if it is seems very different from our own (Japan has an alphabet/language quite different from the U.S.).   This advance preparation allows us to get off the plane and have a sense of what we know and don't know, what questions we will need to ask and where we want to head first.

Previewing a textbook accomplishes much the same thing.   Start by looking at the beginning of your 10-page chunk.  Read section titles.  If no titles, read first lines of paragraphs.  Read the last paragraph.  Glance over charts or photos used on the pages.  Read study questions or summaries that might be given at the end of the chunk of pages.  Now, take a moment to think about what you have just seen.  What do you think will be the main topic of that section?  What do you already know about it from your childhood, past courses or other readings in this current class?  What is your biggest question right now--what more do you need to know?