Sharks are among the oldest animals on Earth. There are hundreds of kinds of sharks. Most are about two meters long. The dogfish shark, however, is less than twenty centimeters in length. A shark has an extremely good sense of smell. It can find small amounts of substances in water, such as blood, body liquids and chemicals produced by animals. {#blank#}1{#/blank#} Sharks eat fish, other sharks, and plants that live in the ocean.

    Sharks grow slowly. About forty percent of all sharks lay eggs. {#blank#}2{#/blank#} Some sharks carry their young inside their bodies as humans do. Some sharks are not able to reproduce until they are twenty years old．Most reproduce only every two years. And they give birth to fewer than ten young sharks. For this reason, over-fishing of sharks is of special danger to the future of the animal.

    Sharks are important for the world's oceans. They eat injured and diseased fish. Their hunting activities mean that the numbers of other fish in ocean waters do not become too great. {#blank#}3{#/blank#} 

    People hunt sharks for sport, food, medicine and their skin. Experts say the international market for some kinds of sharks has increased because many parts of a shark are valuable. Collectors pay thousands of dollars for the jaws of a shark. {#blank#}4{#/blank#} The skin of a shark can be used like leather.  In Asia, people enjoy a kind of soup made from shark fins. Experts say a fisherman can earn a lot of money for even one kilogram of shark fins. Sharks are among the oldest animals on Earth, but some sharks are in danger of disappearing from Earth. {#blank#}5{#/blank#} 

A. Shark liver oil is a popular source of Vitamin A.

B. This protects the plants and other forms of life that exist in the oceans.

C. Sharks are valuable to us and we can make full use of them.

D. These powerful senses help sharks find their food.

E. If too many sharks in one area are killed, that group of sharks may never return to normal population levels.

F. This is a threat to other forms of life in the ocean.

G. The others give birth to live young.

    Eyesight plays an important role in our daily life. Every waking moment, the eyes are working to see the world around us. Over forty percent of Americans worry about losing eyesight, but it's easy to include steps into our daily life to ensure healthy eyes. Here are suggestions for a lifetime of healthy eyesight.

    Schedule yearly exams. {#blank#}1{#/blank#} Experts advise parents to bring babies from 6 to 12 months of age to the doctor for a careful check. The good news is that millions of children now can have yearly eye exams and following treatment, including eyeglasses.

    Protect against UV rays(紫外线). Long-term stay in the sun creates risk to your eyes. No matter what the reason is, it's extremely important to wear sunglasses. {#blank#}2{#/blank#}

    Give your eyes a break. Two-thirds of Americans spend up to seven hours a day using computers or other digital products. {#blank#}3{#/blank#} Experts advise that people practice the 20/20/20 rule: every 20 minutes, take a 20-second break and look at something 20 feet away.

    {#blank#}4{#/blank#} As part of a healthy diet, eat more fruits and vegetables each day. Vitamins C and E help protect eyesight and promote eye health.

    Practice safe wear and care of contact lenses(隐形眼镜). Many Americans use contact lenses to improve their eyesight. While some follow the medical guidance for wearing contact lenses, many are breaking the rules and putting their eyesight at risk. {#blank#}5{#/blank#} Otherwise, you may have problems such as red eyes, pain in the eyes, or a more serious condition.

A. Eat your greens.

B. Eye care should begin early in life.

C. They can properly protect your eyes.

D. Stay in good shape by taking more vitamins.

E. Parents usually don't care about their own eyesight.

F. Always follow the doctor's advice for proper wear.

G. This frequent eye activity increases the risk of eye tiredness.

    Please wear loose clothing, mostly cotton. It is obvious that wearing clothing that is loose rather than tight is welcomed in summer. {#blank#}1{#/blank#}. This carries away the warmth that your body produces and allows cooler air to flow back in.

    {#blank#}2{#/blank#}. When it's really hot out, materials that “breathe” — allowing the flow of air through the fabric (衣料) itself — also work to keep you cool. Cotton and linen are among the most breathable fabrics，so look for clothes made of those substances.

    Your body controls its temperature via a small peanut-shaped section of the brain known as the hypothalamus (下丘脑). {#blank#}3{#/blank#}. It turns the temperature up or down based on various factors — such as how cold or hot the skin is.

    Certain parts of the skin have a larger influence than others. {#blank#}4{#/blank#}. They get their name because you can feel your pulse there, and the reason you can do that is because vessels are so close to the edge of your skin that one can easily hear or feel the flow of blood.

    When you want to lower your body temperature, cooling those pulse points with cold water or ice sends a signal to the brain that says, “Turn cold.” {#blank#}5{#/blank#}. Focus on pulse points that are easy to reach: the insides of your wrists, the area around your temple, and your neck. Holding an ice pack or even a cold washcloth against the skin on these regions will make your entire body feel cooler.

A. It allows air to flow past the skin

B. Sweating helps to cool off the skin

C. These areas are called pulse points (脉冲点)

D. The type of fabric you wear has an influence, too

E. This fools your brain into turning down its thermostat (恒温器)

F. This region works almost like a thermostat in a home

G. Exercising in extreme heat is usually not recommended

    Rivers play an important role on the earth, and we can't imagine what the earth would be like without rivers. {#blank#}1{#/blank#}

    With a length of 6, 650 kilometers, the Nile is the longest river in the world. The Nile River has been the source of human civilization since ancient times. The Nile has two main branches—the White Nile and the Blue Nile. The White Nile starts from the Great Lakes region of East and Central Africa through Lake Victoria.{#blank#}2{#/blank#} The Blue Nile carries with it a lot of fertile soil which turns out to be very important to farming in Egypt.

    The Amazon River is the world's largest river with a width of about 40 kilometers during the rainy seasons but about 10 kilometers wide when it is not flooded. The Amazon River has such a big water volume that it accounts for(占.....比例) more than 20% of all the world's fresh water—far more than any other river. {#blank#}3{#/blank#}The main Amazon River flows mostly through Brazil and Peru but its tributaries can also be found in many other countries.

    {#blank#}4{#/blank#}It has a depth of about 250 meters. Its length is 4, 700 kilometers. The sources of the Congo River are in the highlands and mountains in the Eastern Africa Rift Valley. It's the second largest river in terms of water volume. {#blank#}5{#/blank#}The Congo River basin(盆地) is the catchments(流域，集水区) area of the Congo River. It lies in both north and south of the Equator, making its flow very stable as there are always some tributaries experiencing a rainy season at any time.

A. Some of them are worth mentioning.

B. The Congo River is the world's deepest river.

C. Do you know which is the deepest river in the world?

D. The Blue Nile originates from(发源于)Lake Tana in Ethiopia.

E. Without rivers, there would be no living life in and along them.

F. And it flows through the second largest rain-forests in the world.

G. Streams that begin in the Andes Mountains are its sources.

    Parents often say that they don't mind what their children do in life just as long as they are happy. Happiness and pleasure are almost universally seen as among the most precious human goods.{#blank#}1{#/blank#}Philosopher Jeremy Bentham believed that all sources of pleasure are of equal quality, but John Stuart Mill disagreed. Mill argued for a difference between higher and lower pleasure.{#blank#}2{#/blank#}Lower pleasure, in contrast, requires mere (仅仅的；纯粹的) senses.

    The entire debate assumes a clear divide between the physical and the mental.{#blank#}3{#/blank#}What will it mean for our ideas about pleasure?

    {#blank#}4{#/blank#}Food is usually considered to be the lower pleasure. All animals eat, using the senses of smell and taste. It doesn't require any complex cognition (认知) to conclude that something is delicious. However, these people failed to appreciate something that the French food writer Jean Anthelme Brillat-Savarin captured. That is, "Animals feed; man eats; only the man of intellect(才智) knows how to eat."

    Eating shows that the difference between higher pleasure and lower pleasure is not what you enjoy but how you enjoy it.{#blank#}5{#/blank#}Preparing it using the powers of reflection and attention turns it into a higher pleasure.

A. The dining table is a good place to start.

B. Wolfing down your food is a lower kind of pleasure.

C. What's the real difference between high and low pleasure?

D. What happens if the physical and the mental cannot be separated?

E. All philosophers believed that cookery could never be a form of art.

F. Higher pleasure depends on human abilities such as self-awareness or language use.

G. However, disagreements will be caused about whether some forms of pleasure are better than others.

    Life is filled with regrets (遗憾). Anyone around you will have no difficulty in telling his regrets. As we get older, we look back and wish that we had made better choice. {#blank#}1{#/blank#}

    Make better plans

    If you start to do something, you need to make a plan before doing it. The earlier, the better.

    You will know what comes first and what comes last. {#blank#}2{#/blank#} If changes happen, you can have more time to deal with them.

    Live a more active life

    You can go around more often. More outdoor activities can keep you relaxed and active. {#blank#}3{#/blank#} "Thank you" can bring a smile to someone's face. Learn to say "sorry" and don't be angry with others.

    {#blank#}4{#/blank#}

    A friend may make your life and he or she can break your life as well. So you have to think twice when you choose a friend. Good friends will always give you better ideas. When you get into trouble ask others for help. That little help may get you good results.

    Never fear failure

    Everybody fails. Even the greatest person fails before he or she achieves success. We should not fear failure, because failure is not the end of the road. {#blank#}5{#/blank#}

    Life is good. We don't have to live in our past, but we do hope that we can plan better, live better, and work better when we have the chance to do so.

A. Ask others for help.

B. Find the right friend.

C. You also need to be kind.

D. What can we do to avoid future regrets?

E. Regrets play an important part in our daily life.

F. We must take failure as a chance to learn and improve ourselves.

G. You'll also know what you should do and what you shouldn't do.