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    With the development of Internet, relative services are developed in the form of websites or apps on phones too. Here introduces you Airbnb and Uber.

    1 Airbnb (air Bed and Breakfast)

People can offer or rent rooms for a short time on Airbnb website or its app on smart phones. The cost is usually cheaper than that of hotels. Travelers can book rooms with special activities such as enjoying local music, art and food.

    Airbnb was founded in August 2008, and now it has over two million listings for travelers to choose in the world. The idea of Airbnb, as its symbol shows, is about home and trust.

    2 Uber

    Uber is a ride sharing and taxi app for fast rides in minutes—day or night. It was founded as Uber Cab in March 2009. The Uber app can send an order to the nearest Uber driver, asking him to the location soon. Users can track the car on their smart phones, so they can know when it will arrive.

In August 2016, Uber service was provided in 507 cities and over 66 countries. However, in China, its operation was acquired by Didi in July 2016. The website Bloomberg View said in July 2015 that Uber makes it easier for people to get a taxi.

B

    Most people hope to have a memory which helps them succeed in study, work and life. Can memory be improved? Luckily, hundreds of studies in the past 50 years have already given us a definite answer.

    A healthy lifestyle keeps our brain young and memory sharp. First of all, it is necessary to have a healthy diet. Eating more food rich in B vitamins and vitamin E, such as vegetables and lean meat, helps you have a better memory. Doing exercise can keep your brain alive, too. Proper exercise provides much oxygen for the brain. Running, riding a bike, swimming and even walking two or three times a week are helpful. Moreover, getting enough sleep is important. Only when your brain gets a good rest, can it work well. The healthier your lifestyle is, the better your memory will become. But do not expect a sudden change－it takes a long time to make a difference.

    Memory stills help you remember things better. The following three are the most widely used. Chunking is a way of remembering a piece of information by cutting it into small ones. For example, to memorize a ten-digit telephone number 2127983630, you can divide the digits into three groups: first 212, then 798, and lastly 3630. This method is far more effective than remembering a string of 10 digits. Organization means organizing information into groups of the same kind. For example, trees, grass and flowers are plants; tigers, pandas, horses and cows are animals. Imagery is remembering newly learnt information by using your imagination and connecting it with something that you are familiar with.

    However, memory skills will hardly work if you don't understand the information. What's more, only a regular review can make the memory last long. That is why students are always advised to go over what they have learnt and then use it as regularly as possible.

    Human brains are like muscles that needs nutrients and exercise to become stronger. If you make a few lifestyle changes and try some memory skills, you can certainly improve your memory.

    Here is some information about some of the wonders of the world. I am sure you will be interested in them.

    ThePyramids of Egypt

    There are about eighty pyramids known today. The most well-known was for Pharaoh（法老）

    Khufu. It is known as the "Great Pyramid". It's also the largest one. Workers used about 2.3 million blocks of stone to build it. They spent about 20 years finishing it.

    The Hanging Gardens of Babylon

    The garden sat on a hill. It was a large and wonderful structure（建筑物）. Many parts of the garden were high up on large columns（支柱）. There were many big and green trees with lovely flowers. Although there are many different ideas about the garden, we are not sure whether this wonder ever existed（存在）!

    TheLighthouse of Alexandria

    The Lighthouse of Alexandria was designed about 2,000 years ago. It was in Egypt, too. It was one of the ancient wonders of the world, about 135 metres high. It was once the highest building in the world. Although it doesn't exist now, many people come to see its relic（遗址）every year.

    The monarch is one of the most beautiful butterflies. It is famous for its yearly migration（迁徙）from the northern part of North America to Mexico, There, millions of monarchs spend the winter together in one small area. This migration is one of the greatest wonders of nature. Yet this behavior has now put the monarch at risk.

    Every September, millions of monarchs from the United States fly to Mexico. After about two months of flying time, they reach their sanctuary(庇护所)in central Mexico. Then, in the warm climate of private and quiet valleys, far from most human activity, the butterflies create one of nature's great scenes. They cover every tree with bright color. The show lasts until spring, when the butterflies return north.

    While they are all crowded together, the monarchs are highly weak. If the environment in those valleys was disturbed, the whole species could be hurt or even die out. That is why for many years scientists who knew about the monarchs' winter sanctuary kept the location a secret.

    In recent years, however, the monarchs' secret has been discovered. Today, the butterflies' winter sanctuary is crowded with tourists, who disturb the environment. Worse still, local farmers who need more land to farm have begun to take up the area. They are cutting down trees, making it difficult for the butterflies to survive. They should not farm in the monarchs' sanctuary.

    People should act immediately to protect the species' winter sanctuary. Local farmers must be helped so that they no longer need to take land from the butterflies. Tourist visits to the butterflies' hidden valleys must also be limited. Unless these steps are taken soon, in a few years the monarch butterfly of North America may be just a beautiful memory.

    An atlas is-a book of maps. Atlases are made with different kinds of information about different parts and areas of a country or the world. They are prepared for desk use or travel use.

    Desk atlases are made for different groups of people with different needs. For example, students may use desk atlases to help learn Geography, and other people may use desk atlases to study a place. A popular type of the latest atlas shows the recent fact of the world. New atlases are often carefully produced to help people learn about the changes, such as name changes, boundary(界) changes and other important new information. A desk atlas can also have some different maps of the same place. For example, an atlas may include maps showing population and important products of a place.

    Travel atlases usually show the information about both natural and man-made features(特点). So it is not surprising to find universities, airports, forests, rivers, roads as well as cities, towns and villages in them. A travel atlas is often the first thing people need when they want to start a trip in a strange place.

    It often has a map of a whole country, and a map with more special information of each important place in the country. Take the atlas of the United States as an example, it often has a map of the whole country and then a map of each of the fifty states.

    A travel atlas may also point out the beautiful natural places. In the USA, the atlas may include national parks such as the Yellowstone National Park and some others to show the beauty of nature and interesting places to tourists.