Five years is a short time in the long history of China. But as for the digital world, there are a lot of changes.

    Now we can talk easily with friends on Wechat. When shopping, we needn't carry much cash because most of the stores accept Wechat Pay and Alipay. And online shopping becomes a part of our life. For example, we can buy train and plane tickets on different apps in a minute. If we want to go somewhere, it is easy to find a Mobike as well as a sharing car on the street.

    We may not realize how these changes decide our life, but we never stopped and will not stop moving forward. China decided to set up the Xiongan New Area in Hebei Province on April 1st, 2017. It will be a smart city in China in the future. What's more, robots will play an important role in looking after the old people in five years. In an old people's home of Hangzhou, the robots called Ah Tie work quite well.

    Thanks to the developing digital world, our life is becoming better and better.

    With the rapid development of science and technology, communication methods of people have changed a lot in the past years.

    As we all know, in ancient times, people communicated with people who were far from them only by letters, which took a very long time to get the message.

    In the 19th century, telegraph was invented, but it was not widely used, letter is still the main method at that time. In1836, John Coker invented the first electromagnetic telegraph(电磁电报机) in the world, then telegraph appeared and was popular, which was much faster than letter, bringing great convenience to people.

    As time goes by, telephones become increasingly widely used. Now, the phone has been developed as mobile phone, fixed telephone, Internet telephone and other kinds, being an essential communication tool in the modern information society.

    In addition, network communication is popular as well. It is especially widely welcomed by the youths. A great number of people communicate with others on the Internet by using software, such as email, QQ, WeChat, bbs, MSN and so on. Using software is easy. A computer which is connected to the network is enough. In China, WeChat has become the most popular communication software nowadays. WeChat, known as Weixin in Chinese, is a mobile phone text and voice messaging communication software which is developed by Tencent. People can make video calls that not only can hear the sound, but also can see the people you talk to.

    Have you ever counted the number of digits (数字) in your mobile phone number? Your number has 11 digits. You may sometimes find it hard to remember your number. {#blank#}1{#/blank#} Why is that?

    The 11 digits can be divided into three parts. {#blank#}2{#/blank#} The first three numbers tell you which mobile phone service provider you are using. For example, 135 is for the China Mobile Communication Corporation and 188 is for China Unicom. The fourth to the seventh digits tell you which area the number is recorded in. And the last four digits are random (随机的).

    {#blank#}3{#/blank#} We once had 10 numbers. But as our population grew, there were not enough numbers for us to use. So we began to use 11 digits starting from 1999.

    Eleven digits can be used to make tens of billions of mobile phone numbers, according to the Xinhua News Agency. That's enough for each person to have seven or eight phone numbers to use in China. {#blank#}4{#/blank#} Usually, the service provider will reuse a canceled number after three to six months. If you call a number that you haven't contacted (联络) for a long time, you may find that its owner has changed.

    Besides China, Britain and Japan also use 11-digit mobile phone numbers. But their numbers always start with. {#blank#}5{#/blank#} Countries like the United States, Australia and India use phone numbers with 10 digits. Canada's mobile phone numbers are perhaps the world's shortest: they use seven digits.

    When my friend first arrived in Australia, he saw an old man selling some cheap goods(商品) in the street of Sydney. The old man was one of the poor people in Sydney and in fact there was no difference between them and beggars(乞丐). Most of them were some lonely old people. My friend was a kind hearted man, so he quickly gave some money to him. The old man asked him to pick some goods from him. My friend had no interest in those goods, so he left without choosing. But the old man followed him all the way.

    At first, my friend didn't think a lot, just thinking he would go home. But then when he went very far and saw the old man still following him, he was a little angry, thinking the old man must feel he was kind and wanted more money. My friend turned back and told him with sign language(手语) not to follow him because he didn't have much money.

    But the old man seemed not to understand, speaking something unknown and still following him. My friend happened to meet his Australian friend in the street. Hearing his story, his friend turned to ask why the old man was following his friend. The old man was out of breath, "My son, you gave me money, but you didn't want my things, so I have to give you something. I see you are a foreigner, likely not familiar(熟悉) with our city. I just want to follow you and show you the way. All I can do for you is this..."My friend was surprised. He said he didn't know why, but he felt the old man was just like his father, nice and warm.