阅读下列材料，在空白处填上适当的内容或括号内单词的正确形式。
What should you do if you are not able to sleep? The best thing is to try to avoid bad habits. ___ you always go to bad and get up at about the same time, this sets a ___ (health) rhythm in your life. Don't drink caffeine drinks in the evening. Smoking and alcohol can also keep you awake. You may have trouble ___ (sleep) if you have a heavy meal just before you go to bed.
You may also find it difficult ____ (get) to sleep if you have a problem or something else on your mind. This is ____ you need to relax. As you lie in bed, tense the muscles in your feet and then relax ____. Continue up the body, tensing and relaxing the muscles until you reach the head. Start with the feet again if you are still tense. If you ___ (think) about a problem or about something exciting that is going to happen the next day, get up and write about it. That will help to take it ___ your mind. You can also get up and read, but be sure to choose __book that is not too difficult. ____, you may get so interested that you won’t want to go to sleep even when you feel sleepy.