I love exploring new places. Whether I travel across America or around the world，a new adventure is always waiting. What I don’t always enjoy is the time spent 9,000 meters（30,000 feet）in the air. Tight spaces, long hours, and unexpected-problems can make air travel stressful. Follow these six tips to make your next flight a braze. 1. Make a checklist. Before you pack，make a checklist of everything you need and mark item off as you put them in your bag. Be sure you include important documents, such as your passport. 2. Pack light. You don’t need to pack your whole closet. Choose clothes that mix and match for more variety. Wear your largest shoes on the place to save room in your bag. And pack a few old items that you can leave behind to make more room for souvenirs(纪念品) on the way home. 3. Carry on essential （基本的）items. Unfortunately, dependable baggage service is hard to come by. When you fly, be sure to pack your medicine, important documents, and a change of clothes in your carry-on bag. 4. Pack water and snacks. No one wants to get stuck on a runway for hours without food, water. But bad weather or mechanical problems could leave you stranded（进退两难的）. Pack water and crackers in your carry-on. But leave fresh foods at home. Most countries won’t allow you to bring them across their borders. 5. Stretch your legs. More and more travelers suffer from blood clots caused by sitting too long in tight spaces. You can help prevent this problem by doing stretches in your seat taking short walks every hour. 6. Entertain yourself. A long trip can either mean hours of boredom or an exciting adventure. Plan ahead to keep yourself busy with books，magazines and portable CD player. Just don’t forget to bring extra batteries. Research airlines before you book your reservations. For just a few dollars more，some airlines offer personal entertainment systems. Singapore Air gives you nearly 70 choices of movies，music channels, and other entertainment！ With a little planning ahead，you’ll be able to sit back and enjoy the ride. 68. It is advised by the writer in this passage to _____ for your flight. A. pack all the things you will need    B. leave your important documents behind C. carry some fresh foods with you    D. take some books, magazines and CD players 69. Which of the following tips isn’t mentioned in this passage？ A. Researching airlines before reservations.    B. Staying still during the whole flight. C. Carrying some water and essential items.     D. Making a list of the things you need. 70. The underlined phrase “come by” in tip 3 probably means _____. A. receive by chance    B. obtain by effort    C. pass by   D. offer in satisfaction 71. We can conclude from this passage that _____. A. you will get sick during the long flight hours B. old items are not allowed to bring back on the way home C. you are not allowed to carry things as freely as you want D. you can also board the plane without your passport