Have you ever wondered why birds sing? Maybe you thought that they were just happy. After all, you probably sing when you are happy.
Some scientists believe that birds do sing some of the time just because they are happy. However, they sing most of the time for a very different reason. Their singing is actually a warning to other birds to stay out of their territory.
Do you know what a “territory” is? A territory is an area that an animal, usually the male (雄性) animal, considers as its own. Only he and his family are welcome there. No other families of the same species (物种) are welcome. Your yard and house are your territory where only your family and friends are welcome. If a stranger should enter your territory and frighten you, you might shout. Probably this would be enough to frighten him away.
If so, you have actually scared the stranger away without having to fight him. A bird does the same thing. But he expects an outsider almost any time, especially at nesting (筑巢) season. So he is screaming all the time, whether he can see an outsider or not. This screaming is what we call a bird’s song, and it is usually enough to keep an outsider away.
Birds sing loudest in spring when they are trying to attract a mate and warn others not to enter the territory of theirs.
You can see that birds have a language of their own. Most of it has to do with attracting (吸引) mates and setting up territories.
1. How does the writer explain birds’ singing?| A．By telling a bird’s story. | B．By describing birds’ daily life. |
| C．By reporting experiment results. | D．By comparing birds with human. |
| A．an expression of happiness | B．a way of warning |
| C．an expression of anger | D．a way of greeting |
| A．An area which a bird considers to be its own. |
| B．An area for which birds fight against each other. |
| C．A place where a bird may shout at the top of its voice. |
| D．A place where families of other species are not welcome. |
| A．Because they want to invite more friends. |
| B．Because they want to find outsiders around. |
| C．Because they want to express their happiness. |
| D．Because their singing helps frighten outsiders away. |
| A．The differences of human and birds | B．How birds keep an outsider away |
| C．The reasons of birds’ singing | D．Birds’ singing for happiness |
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【推荐1】How will (将会) the weather be in the future? Some people say they can forecast the weather from animals. If birds are flying high (高飞) in the sky (天空), there will be a nice day. When they sit in trees or stay close together, bad weather is on the way. Ants (蚂蚁) often build (建造) their homes on the steep (陡峭的) side just before the rain comes. Cats like to clean their ears before the rain. Chickens make a lot of noise (发出大量噪音) and run here and there when the rain is coming. Frogs (青蛙) will stay (停留) in the water and make a lot of noise, too. But on a nice day, they are quiet and jump out of the water. Turtles (海龟) often look for (寻找) higher (更高的) ground and cows (奶牛) like to lie down (躺下) when the rain is on the way.
1. What does the underlined word “forecast” mean in Chinese?| A．知道 | B．报告 | C．预测 | D．想象 |
| A．Sunny. | B．Windy. | C．Rainy. | D．Snowy. |
| A．Clean their feet. | B．Clean their ears. | C．Run everywhere. | D．Stay at home. |
| A．Three. | B．Four. | C．Five. | D．Seven. . |
| A．Ants often build their homes on the steep side before the rain comes. |
| B．Chickens make a loud noise when the rain is on the way. |
| C．Frogs will jump out of the water on a nice day. |
| D．Cows like to stand when the rain is on the way. |
【推荐2】Do you see elephants with your own eyes? Do you know about elephants? Elephants are very big and strong.
| A．Usually they live in a group. |
| B．They are bigger than any other animal on land. |
| C．They can lift heavy things with their trunks. |
| D．Now, there are very few elephants in the world. |
| E．What do elephants feed on? |
【推荐3】Plants are very important living things. Life could not go on if there were no plants. This is because plants can make food from air, water and sunlight. Animals and man cannot make food from air, water and sunlight. Animals get their food by eating plants and other animals. Therefore animals and man need plants in order to live. This is why we find that there are so many plants around us.
If you look carefully at the plants around you, you will find that there are two kinds of plants: flowering plants and non-flowering plants.
Flowering plants can make seeds. The seeds are protected by the fruits. Some fruits have one seed, some have two, three or four, and some have many seeds. But a few fruits have no seeds at all. An example of fruit without seeds is the banana fruit.
Most non-flowering plants do not grow from seeds. They grow spores(胚芽). Spores are very small. Some spores are so small and light that they can float in the air. We may say that spores are quite the same as seeds. When these spores are all on wet and shady places, they usually grow into new plants.
1. The main idea of the first paragraph is that________.| A．plants are important for life | B．plants cannot grow without air |
| C．there are many plants in the world | D．we cannot live without water |
| A．flower, water and air | B．water, sunlight and air |
| C．air, water and soil | D．air, sun and light |
| A．Of all living things, animals are most important. | B．Spores are seeds. |
| C．All fruits of flowering plants have seeds. | D．Without plants, man will die out. |
| A．a medicine book | B．a novel |
| C．a science magazine | D．an experiment report |
| A．damaged | B．polluted | C．prevented | D．guarded |
【推荐1】Enjoy Happiness From Sad Music
What would life be like without music? Songs and tunes fill our lives, influencing our emotions, bringing back memories and sometimes making us dance. There is a song for everyone and for every moment, but it seems that it’s sad music that moves us most.
Sad music certainly does its job in making us upset, causing us to feel strong emotions – it’s something we might listen to after a break-up, for example. And a recent study has shown why some people are interested in sad music. Professor David Huron from Ohio State University conducted the research and found the differences between people who love to listen to sad music and those who can’t stand it.
He told the BBC radio programme The Why Factor that it comes down to a natural hormone called prolactin. He says, “As you might have guessed from the name, it’s connected with ‘lactation(哺乳期)’ from breast-feeding. When people cry, they also release prolactin. And, there are circumstances in which prolactin seems to have this comforting effect.” It seems that people who like sad music are maybe getting too much prolactin, or more than is normal, and when they hear sad, downbeat music, it gives them a good feeling. But if prolactin isn’t released, or there isn’t enough of it, some people find that sad sounds don’t help to cheer them up.
Previous research by Durham University has also suggested that listening to sad music can lead to pain and sadness; but it can also provide comfort and even enjoyment. A high number of people they surveyed were cheered up by listening to sad songs. Though the feeling may not be exactly the same as happiness, it may be the ability to deal with the sadness that gives the feeling of comfort.
So, reacting to sad music on the radio may have nothing to do with the melancholic sound of a piece of music, but rather a natural chemical reaction taking place in our bodies. Maybe that explanation is music to your ears if you’re wondering why you’ve been listening to Billie on repeat!
1. The writer thinks ________ can touch people a lot.| A．soft music | B．sad music | C．rock music | D．metal music |
| A．The way to enjoy sad music. |
| B．The audience who prefer sad music. |
| C．The reason why sad music touches people. |
| D．The researchers who participated in the study. |
| A．Awful. | B．Blue. | C．Magic. | D．Soft. |
【推荐2】For most people, the word “fashion” means “clothes”. But people may ask the question, “What clothes are in fashion?” And they use the word “fashionable” in the same way. “She was wearing a fashionable coat. His shirt was really a fashionable colour.”
But of course there are fashions in many things, not only in clothes. There are fashions in holidays, in restaurants, in films and books. There are even fashions in school subjects, jobs ... and in languages.
Fashions change as time goes. If you look at pictures of people or things from the past, you will see that fashions have always changed. An English house of 1750 was different from one of 1650. A fashionable man in 1780 looked very different from his grandson in 1860.
Today fashions change very quickly. Some of this is natural. We hear about things much more quickly than in the past. Newspapers, radios, telephones and televisions send information from one country to another in a few hours.
New fashions mean that people will buy new things, so you see there is money in fashion.
1. Today fashions change very quickly because ________.| A．people read newspapers every day |
| B．radios send information from one country to another |
| C．new things that people like are often shown on TV |
| D．people quickly learn what is happening in the world |
| A．three | B．four | C．five | D．six |
| A．the changes of fashions |
| B．the kinds of colours |
| C．the money in fashion |
| D．the differences between houses |
【推荐3】Do you know about bioplastic (生物塑料)? It is a kind of plastic. But it is different. Normal plastic is made from chemical materials and takes a very long time to degrade (降解). But bioplastic is good for the environment. It is made by using bacteria (细菌) to process natural sources like vegetable oils, corn or sugar. It can degrade more easily.
But there is a problem with bioplastic. The “food” that bacteria eat is also what we eat. This means that bacteria are competing against humans for the same.
Now scientists have found a new way to make bioplastic using two kinds of bacteria and sunlight, according to Newsweek.
One of the bacteria is called synthetic cyanobacteria (合成蓝藻), which can use sunlight to produce sugar. The other kind is Halomonas boliviensis (玻利维亚盐单胞菌), which lives in the salty waters of Bolivia. It eats the sugar that the first bacteria produce and then it can produce polymers (聚合物). Polymers are used to create bioplastics. The way the bacteria store polymers is similar to how humans store fats.
Producing bioplastic with these two bacteria has many advantages. It is 20 times faster than the normal way we produce bioplastic. Also, using these two bacteria saves resources.
First, producing large numbers of bioplastic requires corn and sugar, which are used to feed normal bacteria. And growing corn and sugar needs farmland. But these two special bacteria can just use sunlight. The land that is saved can be used to grow food for humans.
Besides, this process doesn’t need rich land or clean water at all, scientists said to Newsweek. The next challenge scientists face is that they want to put their lab research into real-world practice. By doing this, bioplastic made with these two bacteria can be widely produced in the future.
1. Compared to normal plastic, bioplastic __________.| A．is easier to process | B．uses more materials |
| C．produces no waste | D．is easier to degrade |
| A．Humans might have less food to eat. |
| B．It helps spread harmful bacteria. |
| C．People are afraid to use bioplastic. |
| D．It leads to the overuse of chemical materials. |
a. eating the sugar b. creating bioplastics
c. producing polymers d. using sunlight to produce sugar
| A．a-d-c-b | B．a-d-b-c | C．d-a-c-b | D．d-c-a-b |
| A．It only requires farmland. |
| B．It saves time and resources. |
| C．It helps kill harmful bacteria. |
| D．Its process produces lots of fats. |
| A．A New Kind of Plastic | B．Advantages of Bioplastic |
| C．A Way to Store Fats | D．Two Kinds of Bacteria |
【推荐1】My family makes the best chicken salad. Dad prepares all of the ingredients（原料）and Mom makes the relish（调味品）. There are a few things that make this chicken salad different from the other chicken salads. First, we use fruit jam（果酱）in the relish. You can buy any fruit jam, like banana jam or orange jam. But we have bottles of strawberry jam that my mother made, so we use the strawberry jam. Second, we put some green olives（橄榄）. Green olives give the salad an interesting taste and make a big difference. Now let me tell you how my family makes the salad.
First, mix up all of the salad ingredients in a large bowl. The ingredients are chicken, tomatoes, green olives, onions and apples. If you like lettuce, you can also put some. Next, make the relish. Please mix the jam, the juice and the salt. Finally, mix the relish with the salad ingredients.
Do you have a favorite chicken salad recipe? Please tell us about it. You can write to greensalad@yahoo. com.
1. What kind of jam does the writer’s family use?| A．Strawberry jam. | B．Banana jam. | C．Orange jam. | D．All kinds of fruit jam. |
| A．green olives and chicken | B．green olives and a different relish |
| C．lettuce and a different relish | D．chicken and a different relish |
| A．call | B．write an e-mail to | C．visit | D．send a letter to |
| A．the writer’s favorite dish | B．all kinds of fruit salads |
| C．a different chicken salad | D．the writer's family |
【推荐2】Anyone can get lost while playing in the wild. It might happen to both kids and adults. Do you know what to do if you get lost?
The first thing you can do is to tell someone about your plan.
Last, always carry some water and food.
| A．You can bring a dog friend with you. |
| B．Here is some good advice for you. |
| C．They can provide you with energy when you are lost. |
| D．As a teenager, you should tell your parents where you are going. |
| E．Another great thing you can do is to go somewhere with your friends. |
【推荐3】Bananas are known as the most important fruit and income for millions of people in lots of areas across the world. However, British scientists said that the fruit may disappear by 2050.
One reason for this is climate change. Scientists at the University of Exeter collected data from 27 countries that produce 86 percent of the world’s bananas. They found that climate change has improved growing conditions in 21 of these countries. For the past 60 years, the average yield（平均产量）has reached 1.37 tons of bananas per hectare（公顷）.
However, if temperatures keep rising, this advantage will disappear. Ten of the countries, including India, the world’s biggest producer of bananas, will produce fewer bananas. By 2050, the fruit may die out.
Shouldn’t bananas grow more easily if it’s hotter outside? In fact, the perfect temperature range for growing bananas is between 24°C and 32°C. If temperatures get too high, they will stop growing.
Diseases are another danger to bananas. Unlike other crops, the bananas we grow come from shoot cuttings（茎段）rather than seeds. This means that all banana plants have the same genotype（基因型）. In other words, if a disease is able to kill one plant, it could kill them all.
One serious disease is called Panama. Caused by fungi（真菌）in the soil, it has spread across South Asia, Africa, the Middle East and Australia. If one banana plantation（种植园）suffers from the disease, it will take 30 years until it is able to grow bananas again. Scientists haven’t found a cure for this disease.
1. What does the underlined word “this” in Paragraph 2 refer to?| A．People’s love for bananas. | B．The most important fruit crop. |
| C．The future disappearance of bananas. | D．The importance of growing bananas. |
| A．Bananas won’t be as tasty as now. |
| B．More countries will start to grow bananas. |
| C．Bananas will grow better in most countries. |
| D．Bananas will not be able to grow any more. |
| A．How bananas are grown. | B．Which diseases can kill bananas. |
| C．Why diseases can easily kill bananas. | D．What diseases bananas may suffer from. |
| A．Fungi in the soil help bananas have the disease. |
| B．A plantation with the disease can grow bananas next year. |
| C．Scientists have found the way to deal with the disease. |
| D．It’s hard for the disease to spread from one place to another. |
| A．offer tips for growing bananas | B．explain why bananas may die out |
| C．describe bananas’ growing conditions | D．show the difficulties of growing bananas |
