What are you going to do if you are in a burning building？How will you escape？Do you know how to save yourself？ Please read the following passage.
    Escaping a fire is a serious matter. Knowing what to do during a fire can save you life. It is important to know the ways you can use and show them to everyone in the family, such as stairways and fire escapes, but not lifts.
    From the lower floors of the buildings, we can use windows. We should learn the best way of leaving through windows with the least chance of serious injury.
    The second floor window is usually not very high from the ground. An average person, hanging by the finger-tips will have a drop of about six feet to the ground. It is about the height of an average man. Of course, it is safer to jump out in a right way than to stay in a burning building.
Windows are also useful when you are waiting for help. Be sure to keep the door closed, or smoke and fire may be drawn into the room. Keep your head low at the window to be sure you get fresh air rather than smoke that may leaked（渗）into the room.
On a second or third floor, a person can escape through a window that open onto a roof. Then from the roof drop to the ground. Dropping onto cement（水泥）might end in injury. Bushes（灌木丛）and grass can help to break a fall.

    On June 26th, 2000, two scientists, called Francis Collins and Craig Venter, told the world that they could now read the whole “map” of the human body: DNA. DNA is something that all humans have, and it tells the body what to do. DNA is the reason that we look like our mother and father, because we get some of their DNA to make our own. Now we can read some of this “map”, and so we can find out more about how our bodies work.

    People have been trying to understand the human body for a long time. In 1860, Gregory Mendel discovered that there is a special reason why we look the same as other people in our family. It is because of small things called “genes” that we have in our body. In 1953, James Watson and Francis Crick made another discovery and found out that those small parts are really messages written in the DNA with a special language.

    In 1961, Marshall Nirenberg and Johann Matthaei found the first “word” that they could understand in that language, showing how DNA tells the cell to build its parts. This meant that one day we would be able to read all the messages that a human body gets from its parents' bodies. Scientists have now found all the words in DNA map, but we still do not understand what they all do. By understanding what just one “word” means, we can help save people from several diseases. So the more we understand, the more doctors will be able to do.

    Most people hope that this will help to make better medicine and help people who are very ill. Other people worry about that when we learn more words and find out lots of other information, we still use it in the wrong way, just to make people more attractive, or stop sick people getting jobs.

    Most American children eat potatoes. But many children don't know what of the potato is the best food. Take a knife and cut from the middle of the potato a piece as thin as paper. I hold the piece between your eyes and light. You will see that the potato has skin(皮), an outside rim(边缘)and an inside part. The outside rim which is right under the skin of the potato, is the most valuable part of all. But this is often thrown away with the skin. Even the skin itself is better for food than the inside. When eating a cooked potato, if you choose the inside and leave the outside, you are throwing the best part of it. If you can't cat the whole potato, eat the outside rim first and leave the inside part.

    Technology is developing fast and it has become an important part of our life. Then what will the world be like in the future?

    3—D food will be both delicious and nutritious(有营养的). We can use 3—D printers to print some basic materials.    ①    And we can go further. Scientists belive that we just need to turn on a printer in the kitchen and then we can enjoy our favourite food whenever we like.

         ②      5G network will allow many more people to get information. Big companies like China Mobile and China Unicom will start to offer 5G. It is said that promises download speeds 10 to 20 times faster than 4G. For example, we can download a film within just 1 second. But with a 4G network, it takes a few minutes. There will be much bandwidth (带宽) and we can get unlimited (无限的) information.

    Underwater cities will provide more space. The earth is becoming more and more crowded. We may turn to underwater homes, which will be built as low as 15 of the sea can be used to provide power for the homes.

         ③      For us common people on the earth, the dream of travelling around space will come true. In the coming years, spacecraft will be as popular as buses, trains and planes. We can leave our home and enter space to take an adventure (冒险). And even we will get used to living there.

    A robot will be a part of life.  Robots can do many of the same things as we humans do like driving cars. But they will be used in other areas as well. They will be able to think. They can tell the difference between right and wrong. They can feel       ④        In a word, just as Jules Verne said, "Anything one man can imagine, other men can make real."

    People in Western countries are eating less meat these days, whether for their health or because they want to protect animals. But now they have another reason.

    Eating less meat can help to prevent climate change, according to a recent study published in Nature.

    Raising livestock (家畜) is bad for the environment. When animals like cows digest (消化) food, their stomachs make greenhouse gases, which are a major cause of global warming. Seventeen percent of greenhouse gas emissions (排放) come from livestock farming, The New York Times reported.

    In addition, to raise these livestock, people have to cut down forests and turn them into farms. Forests play a key role in fighting global warming because they absorb greenhouse gases.

    Eating less meat according to certain guidelines could cut global food-related emissions by nearly a third by 2050, the study found. Maintaining (保持) a vegetarian diet in the long term could bring down emissions by 63 percent.

    But eating less meat won't be easy. According to the study, people in Western countries will need to eat 90 percent less meat than they do now in order to have an impact (影响) on our climate. Scientists are now trying to find new foods to replace meat.

    Some say that insects (昆虫) could help. A 2013 UN report said that eating insects is healthier and better for the environment. They produce 75 percent less greenhouse gases than livestock.

    Some experts are creating lab-grown meat. They make meat in a lab using livestock cells (细胞). In March, US company JUST said people in the US might be able to buy its lab-grown meat by the end of this year.