Every year, millions of birds are killed or hurt when they fly into buildings. Why does this happen?  Birds are flying into windows and tall buildings that are all covered by glass.

Many birds fly from one place to another. Most of the time, they live in the wild, such as forests and wetlands.  They might see small trees and flowers inside a window and want to rest on these plants. The birds do not know there is glass between them and the plants.  

Some birds fly at night. They use the moon and stars to help guide them in the right direction. Tall buildings with lights on at night can confuse（迷惑）the birds.  The birds see the light, but they cannot tell that the light is coming from inside a building. They fly toward the light and crash into a building. On many mornings, there might be several dead birds lying on the ground.

  Many office buildings now turn off their lights at night. This helps reduce the number of birds that fly into buildings and it also helps save energy.

There are more than 35 million teenagers who are between the ages of 13 and 19. They want to be free and independent. Many teenagers disagree with their parents about how much freedom they should have. Some disobey their parents. 

Today American teenagers spend a lot of money buying records，clothes and electronic devices. Last year teenagers spent almost 100 thousand million dollars. Where do the American teenagers get all this money？Many of them have part﹣time jobs. Some work as baby﹣sitters. They make about 4 dollars an hour. Some teenagers do not have jobs. Instead，they receive money from their parents. They might get as much as 20 dollars a week. 

That one looks like a rabbit. Or is the larger one a whale? Whatever shape they take, they're clouds. So what are clouds, exactly? 

●Clouds are floating (浮动的) water.

Clouds are made of small water drops. Each drop is made of many flying water molecules (分子). They stay together around a tiny piece of dust (尘埃) or salt. How small are cloud drops? A shoebox of clouds might hold millions of cloud drops.

·

Clouds look light and soft, but they hold much water. And water is heavy. The water in an average cotton-ball cloud may weigh as much as a group of elephants.

·Things live in clouds.

Have you ever dreamed of living on a cloud? It would probably be cold and wet, with no place to sit down. But weather balloons have discovered insects inside clouds as high as 20 miles above the earth.  Airplane pilots have ever found butterflies at 10,000 feet.

·Clouds don't last.

Clouds are always changing. They form and then change into gas soon. They are changing shapes as the wind blows them across the sky. Will the shapes stay long? But some small soft clouds often last 10 minutes.

So take a look at the cloud before it disappears—what does that cloud look like?

A. Clouds are heavy.

B. Clouds look like elephants.

C. Some big clouds can hang around all day.

D. The following can help you know more about them.

E. Most of the insects inside clouds are blown there by the wind.

Birds are the only animals that have feathers. Feathers are the coat a bird wears on its body，just like the hair most of other kinds of animals wear on their bodies. We，human beings，don't depend on feathers or hair to keep us warm，as birds and animals do，we have our clothes. The feathers and shapes of the birds help us to tell one kind from another. Feathers come in beautiful colors. 

Many birds use colors to hide from enemies（敌人）. This is called camouflage. All birds molt（换毛），but the ptarmigan molts twice a year，changing color to go right for the season. In winter，when snow is on the ground，it has white feathers. In spring，it molts and grows brown feathers that match up with the land，grass，trees or other conditions where it lives. When winter comes，it molts again and grows white feathers. 

Besides feathers，birds can have good voices and are good at singing. Many birds，such as the robin，sing to send messages to other birds. Each type of songbird has its own song. By singing，birds show who they are and where their land is. In spring，many birds sing together loudly at daybreak. The sound they make is known as the dawn chorus，so﹣called"early morning singing of love" by many people in a Chinese yet simpler way. 

A major development to self-driving cars may change the way we will drive in the future. Google, the leading company in self-driving technology, has changed its development plan. It had driverless cars built by car factories, but now will start building its own cars.

Google has started to build some kinds of experimental electric self- driving cars that look like a Smart car or Fiat 500. There is no steering wheel (方向盘)，gas pedal (油门) or brake (刹车). The only thing a human passenger controls is a red "e-stop" button for fear stops and a start button. The car's only "friendly" face is designed to make it help people accept self-driving technology.

Google workers took part in a long experiment, in which they used self-driving cars for their usual travel to work. No accident happened, but Google's heads realized that depending on a human passenger to drive in an emergency wouldn't work because they may be reading, working, or sleeping. Now the self-driving car drives by itself if the driver takes his hands off the wheel for over ten seconds.

Google's self-driving cars are now limited to a speed of 25 miles per hour for safety reasons. The cars aren't allowed to drive on highways. However, a Google engineer said that once the cars are solved to run safely, we can drive at the speed of 50, even 80 miles an hour.

Google recently announced that its cars had covered 700,000 miles of public roads, and they were now running in busy city streets. People who love self-driving cars say this will improve transport by making roads safer, cutting down accident, and making less pollution.

There is an English saying,"Laughter is the best medicine. " Until recently, few people took the saying seriously. Now however, doctors have begun to look into laughter and the effects it has on the human body. They have found that laughter really can improve people's health.

Tests were carried out to studythe effects of laughter on the body. People watched funny films while doctorschecked their heart, blood pressure, breathing and muscles. It was found that laughter has similar effects to physical exercise. It increases blood pressure, makes the heart beat quicker and makes people breathe deeper; it also works several groups of muscles in the face, the stomach, and even the feet. If laughter exercises the body, it must be beneficial. 

Other tests have shown that laughter appears to be able to reduce the effect of pain on the body. In oneexperiment doctors produced pain in groups of students who listened todifferent radio programmes. The group that tolerated (忍耐) the pain for the longest time was the group which listened to a funny programme. The reason why laughter can reduce pain seems to be that it helps to produce a kind of chemical in the brain which diminishes both stress and pain. 

As a result of these discoveries,some doctors in the United States now hold laughter clinics, in which they help to improve their patients' condition by encouraging them to laugh. They have found that even if their patients do not really feel like laughing, making them smile is enough to produce beneficial effects similar to those caused by laughter.

Every year, millions of birds are killed or hurt when they fly into buildings. Why does this happen?  Birds are flying into windows and tall buildings that are all covered by glass.

Many birds fly from one place to another. Most of the time, they live in the wild, such as forests and wetlands.  They might see small trees and flowers inside a window and want to rest on these plants. The birds do not know there is glass between them and the plants.  

Some birds fly at night. They use the moon and stars to help guide them in the right direction. Tall buildings with lights on at night can confuse（迷惑）the birds.  The birds see the light, but they cannot tell that the light is coming from inside a building. They fly toward the light and crash into a building. On many mornings, there might be several dead birds lying on the ground.

  Many office buildings now turn off their lights at night. This helps reduce the number of birds that fly into buildings and it also helps save energy.

Brainstorming is the practice of coining up with ideas or solutions. But we do have some rules to follow for successful brainstorming.

Focus on quantity （数量）over quality. When it comes to brainstorming, the more ideas, the better.

Don't worry about the quality of your ideas for now. Remember that your goal is to come up with as many ideas as possible. Even if none of them are perfect, you'll still have many creative ideas to use for your final plan.

Encourage big or unusual ideas. Although unusual ideas may not be immediately practical, just creating those ideas gives your brain training. It can also help to produce creative solutions that are hard to come up with.

Don't say no to the ideas of others. You can put together the best parts of different ideas to create new, even better ones. Even if you're not brainstorming as a group, you should still think about sharing your ideas with others and asking them for their advice.

You don't have to regard yourself as a very creative person to come up with excellent ideas and solutions at once. Even if you don't find the perfect solution, just practicing it can help to improve your creativity. Put these tips together and you are sure to come up with some great ideas.

Connecting with Nature

How do you feel when you hear birds singing freely in the trees? What's your feeling when you see butterflies dancing slowly and lightly in the wind? Whether you love researching the outdoors or watching far away, getting close to nature can take your mind off your worries and make you feel relaxed.

What is nature?

Nature means the world around us that is not man-made, including birds, mountains, trees, the sea and the stars. It's also a force that controls things like weather. We can find nature wherever we are and wherever we go —beaches, gardens, parks, rivers, and even unexpected places like cracks (裂缝) in the stones.

Why does nature make us feel good?

Spending time in nature brings peace, joy and wonder to our lives. It takes us outdoors, gets us active and lets us care more about the environment. Even a little gift of nature can make us feel free and hopeful, such as breathing in fresh air, listening to the wind in the trees or standing at a mountain. Ralphie, who is 10, likes being close to nature on a bike with his family. He says, "It makes us feel happy and takes our mind off things because we have to pay attention. We are away from traffic and we hear more birdsong and see more wild animals."

How can we feel closer to nature?

Feeling closer to nature is easy. We can build a connection with nature wherever we are using our senses. Try listening closely to birdsong, smelling flowers and feeling sand between our fingers. Paint a picture and take photos of the natural places that we like best. They may help us feel closer to the natural world. It's important to try and connect with nature, notice its beauty and how it makes us feel.