根据短文理解，完成下列各题。
    In every school there is "top" crowd that sets the pace, while the others follow their lead. For example, if the crowd decides that it is smart to wear bright red sweaters, then very soon everybody is wearing bright red sweaters.
    There is nothing wrong with that, except the fact that for some people bright red sweater is really unsuitable.
    The situation can even become dangerous, if the top crowd decides that it is smart to drink and to drive cars at seventy miles an hour. Then the people who follow the lead are endangering their lives. They are like the sheep being led to the slaughter(屠杀).
    Now it's possible that you have come across situations like these more than once in your life. In fact you probably did something you knew to be wrong one time or another. You may have excused yourself by saying, "Gee, the crowd does it."Well, let the crowd do it, but don't do it yourself. Learn to say "No".
    Develop your own standards(标准)and your own judgment. If you know the crowd is planning something you disagree to, you'd better take the courage to bow out in a polite way. You'll have the satisfaction of standing on your own two feet.

阅读理解

B

    Animals grow up in different ways. Some newborn animals are helpless but their mothers protect them. A newborn kangaroo is very small. It is only a few centimeters(cm) long. It closes its eyes and doesn't have hair. It stays safe in its mother' s pouch(育儿袋) for a long time.A newborn monkey can not walk. Its mother carries it everywhere.

Other baby animals can walk soon after they're born. They learn to run with their mothers when danger is near. A baby zebra can run, an hour after it is born.

    Some baby animals are born in a place that is safe. Baby wolves are usually born in big holes with little light. Other baby animals are born in the open. A baby elephant is often born on open land.

    Animals that drink their mothers' milk are called mammals. A mother bear's milk is rich. Baby bears have milk for a few months. This is the same with baby zebras. As baby animals grow, they need solid(固体) food. Baby lions eat what their mother can catch!

根据短文理解，选择正确答案。

What are fossils?

    Fossils are the remains of plants or animals. For such remains to be considered fossils, scientists have decided they have to be over 10,000 years old. The word fossil comes from the Latin word “fossilis”, which means, “dig up”.  Fossils can be divided into “body fossils” and “trace(痕迹) fossils”. Body fossils are the remains of a plant or animal's body. Trace fossils are the remains of the activity of an animal, such as footprints, egg shells, and nests.

How are fossils formed?

    Some animals were quickly covered after their death by sediment(沉淀物) like earth, mud or sand. Over time, the parts of the animals that didn't rot (usually the harder parts like bones and teeth) were covered in the newly formed sediment. Then, a lot of chemical changes happened to the animals bodies. Water with minerals(矿物质) went into the bone and took the place of the chemicals in the bone with rock-like minerals. In the end we get a heavy, rock-like copy of the original object - a fossil. There weren't any changes in size and shape when an object changed into a fossil, but the fossil of a bone doesn't have any bone in it! It is chemically more like a rock! According to scientists, fossils have been found on every continent(大陆) on Earth.

    In England, people often talk about the weather because they can experience (经历) four seasons in one day. In the morning the weather is warm just like in spring. An hour later black clouds come and then it rains hard. The weather gets a little cold. In the late afternoon the sky will be sunny， the sun will begin to shine， and it will be summer at this time of a day.

    In England， people can also have summer in winter， or have winter in summer. So in winter they can swim sometimes， and in summer sometimes they should take warm clothes.

    When you go to England， you will see that some English people usually take an umbrella (伞)or a raincoat with them in the sunny morning， but you should not laugh at them.

    If you don't take an umbrella or a raincoat， you will regret (后悔) later in the day.

    ①What does the city of the future look like? Flying cars? Robots? Or smog（烟雾）-eating buildings?

    ②Arconic, an American company, has made plans to build a 4.8-kilometer-high skyscraper（摩天大楼）. It says that the super tall building can clean not only itself but also the air around it by “eating” smog and pollutants（污染物）. But how is it done?

    ③Sherri McCleary, s scientist at Arconic, says they have introduced a new technology called EcoClean. It is a special coating that pulls pollutants out of the air. With a little help from sunlight and water vapour（水蒸气），the coating will produce atoms（原子能）called free radicals（自由基）. It is these free radicals that will take in air pollutants, break them down, and then leave the air cleaner.

④But “eating” smog and pollutants is not the only thing this skyscraper is able to do. In fact, thanks to 3D printing, the materials the building used will become even better and stronger—not only making the skyscraper look more modern, but also make it possible to stand strong winds and terrible weather.

    ⑤However, some people don't think it will work out well. Air pollution has its own character and it harms lots of cities. Does the smog-eating building have such a magical ability to stop the pollution? It seems impossible to bring the pollution under control in a short time. We should prepare ourselves for a hard fight against the pollution.

    ⑥Sounds impossible? Anyway, Arconic believes a skyscraper of this kind will be built by 2062.

    A black hole is a place in outer space with very strong gravity. Gravity is a great force(力量) that shapes the universe. On Earth, gravity makes apples fall from trees. It keeps your feet planted on the ground. The gravity in a black hole is much stronger. It is so strong that nothing around it can get away from it, not even light.

    Black holes are invisible. We can't actually see them because they don't throw back light. But scientists can find them with space telescopes(望远镜)and special tools. The strong gravity makes nearby stars move in a certain way. By studying how the stars move, scientists can find out if they are flying around a black hole. Strange things happen around black holes. This makes black holes a popular subject of science fiction(科幻)stories, although they are very real.

    A black hole forms when a star dies. The star falls in on itself and turns into a very small point. Because of its small size and huge mass(质量), the gravity will be so strong that it will pull light in and become a black hole. Black holes can grow huge as they continue to pull other things in and "eat" them. Many scientists believe that there are super-massive black holes at the center of galaxies, including the Milky Way.

    The idea of the black hole was first suggested by two different scientists in the 18th century: John Michelle and Pierre-Simon Laplace. In 1967, a physicist named John Archibald Wheeler came up with the name “black hole". Studying black holes can tell us many things about our galaxy and help scientists answer questions about the universe.