According to the passage, if we don’t have a schedule,______.

The words "timetable" and "schedule" make most final year students want to eat their own vomit. Unfortunately, the harsh reality is that final year students must develop a timetable. If you don’t have a schedule or plan for studying, you will have no way of allocating your valuable time when the unexpected arises. A well-thought-out timetable can be a life saver. It is up to you to learn how to develop a schedule that meets your needs. Change it if necessary, but most important, follow it. All timetables should be made with the idea that they can be changed. A good one will keep you from wandering off course.
    A good timetable should make every hour count—every class, social events and other activities you engage in. You must focus on the other "free time" available and how you will use it. Make a weekly schedule and divide each day into one-hour increments. Indicate times for classes, socializing, and work time. Also block off a period for sleeping every day. In the precious hours left over, plan time for study. This gives you a rough road map of the time available. Of course, you can change your schedule as circumstances need.
    The timetable you develop should guide you in how to distribute the available time in the most productive manner. Sticking to your schedule can be tough, but don’t dribble away valuable time. Avoiding study is the easiest thing in the world. It is up to you to follow the schedule you’ve prepared. A good deal of your success in high school and with any future study depends on this simple truth.