题目

规定“✴”是一种新的运算法则，满足：✴＝．       示例：4✴（－3）＝42－（－3）2＝7． （1）求2✴6的值； （2）求3✴[(2)✴3]的值． 答案：Being a teenager can be challenging， but it can also be exciting． You're becoming more independent（独立的）and making decisions for yourself． You are also bearing to take risks and solve problems better． And changes are happening throughout your body， even in your brain．The changes in your brain are influencing how you develop into an adult． Imagine the structures（结构）of your brain is like a big road map． Lots of roads lead to different destinations（目的地）． When you were a child， as you learnt new things， your brain created more and more roads to different destinations． By the time you become a teenager， many different roads lead to the most important places on the map． Now your brain's job is to make that map more efficient（有效的）．As a result， your experiences as a teenager actually influence the way that your brain develops． If you spend hours playing video games， what skills do you use？ You learn to see something with your eyes and respond（作出反应）to it with your hands． As you develop those skills， your brain is making sure that the roads leading to them are especially fast and efficient． So， your video﹣game playing could be preparing you for a career such as a pilot．This is a great time for you to practice new skills and discover what you're good at and try what you love doing． Go out and try different activities， and stick to them if you think they are useful． Remember that with everything you do， you're shping your brain for the future．1.What happens as children learn new things？ A. Their brains make the maps more efficient．B. The structures of their brains are like big road maps．C. Many different roads lead to the most important places．D. Their brains create more roads to different destinations．2.What's the writer's advice for teenagers？ A. Teenagers should experience more and stick to the useful activities．B. Teenagers should play more video games in order to be a pilot．C. Teenagers should work harder and more efficiently．D. Teenagers should learn to be more independent．3.Which of the following would be the best title of the passage？ A. Ways of Chnging Your Brain．B. Making Decisions for Yourself．C. Developing Your Brain for the Future．D. Changes Happening in Your Brain． 1.D 2.A 3.C 【解析】 文章大意：这是一篇日常生活类阅读，主要介绍作为一个年轻人要具有挑战性，这样去锻炼你的大脑，去学习冒险和更好地解决问题。尝试练习新技能，在好时间做喜欢的事情，尝试不同的活动，并坚持下来，这对塑造你的大脑，对你未来的发展有好处。 1.细节理解题。根据第二段第二行When you were a child as you learnt new...