My parents have always said they felt uncomfortable traveling by train when they were my age. When they talk about the crowded and airless rain carriages (车厢), I just always can’t imagine how it feels to travel by train like that.

However, train travel is quite a different experience today and the train service has improved greatly, especially when the high-speed rail (HSR) service has been widely out into use in China. HSR refers to (指) any railway in China with a speed of 250 km/h or higher. The high-speed rail has experienced rapid development since our country started to run its first high-speed train between Beijing and Tianjin in 2008. The environment in the high-speed trains is the same as that in an airplane. Now the high-speed rail in China is really fast, convenient and comfortable

Recently, Chinese people have become known for their speed of developing and making changes. Such a high speed is known as China Speed. The development of the high-speed rail has let me realize what China Speed is. However, China Speed means a lot more. We’ve seen so many tall buildings show up almost overnight. It took us only several tens of years to go from the difficulty of traveling to roads and highways connecting every comer. Mobile phones with 5G technology show more and more importance in everyone’s life. China Speed has made a difference to our country and even the world.

But as we enjoy China Speed, we should also be serious about the problems it has brought to us, such as environmental pollution and the imbalance (不平衡) of development. It is our responsibility to bring China a better future.

Do you know about Artificial intelligence (AI) (人工智能） ?   

AI is growing very fast now. AI is a group of technologies that help machines get, understand and use information to do tasks. AI’s recent developments have got a lot of social attention. Some people have welcomed AI because it makes things possible. For example, AI will have a big influence on areas like medicine and engineering. But this attention has also produced a lot of fear. Especially, many workers are worrying that AI could make them lose their jobs.

According to a recent study, nearly five percent of jobs will disappear because of AI. In some industries, AI is already doing the work that people used to do. Self-driving cars and trucks controlled by AI will also take away the drivers' jobs in the future.

On the other hand, AI will also create many new jobs for people. More people will be needed to write programs for AI systems (系统）and they will set up and work on them, too.

Meanwhile, jobs that require feeling, excellent communication skills with people will not be replaced (取 代) by AI. These include jobs in fields like teaching, nursing and personal training.

AI is here. It is changing how people live and work in many ways. That makes AI important to watch, not to fear.

Nowadays electronic devices are becoming wireless (无线的). We can listen to songs by using earphones without wires. A mouse or keyboard can be run on a computer without wires. Many of them use Bluetooth. Bluetooth is the technology that allows the exchange of data between different devices. However, have you ever wondered why it is called Bluetooth?

Bluetooth was named after Harald Bluetooth, a 10th-century king of Denmark (丹麦). He was famous for uniting Denmark and Norway into one kingdom. His dead tooth, which was a dark blue color earned him the nickname Bluetooth. In 1996, Jim Kardach from Intel suggested Bluetooth as the name because King Harald Bluetooth united two kingdoms just as people wanted to connect computers with other electronic devices. The Bluetooth logo is a combination of Harald’s initials (首字母) ‘H(ᚼ)’ and ‘B(ᛒ)’ written in Nordic runes (古代北欧文字).

Developed in the late 1990s, Bluetooth has become increasingly popular. On May 20, 1999, the Bluetooth Special Interest Group (SIG) was set up and the first Bluetooth specification (标准), Bluetooth 1.0, was published in the same year. The Sony Ericsson T36 became the first mobile phone to include Bluetooth in 2001. The Bluetooth SIG published the latest Bluetooth 5.3 on July 13, 2021.

Besides Bluetooth headsets, there are more things people can do with Bluetooth. Bluetooth can connect up to seven devices to one master device at the same time and allows users to exchange voice and data transmissions (传送) between two or more devices. For example, we can print wirelessly across the room with a Bluetooth printer. Without Bluetooth, each device would have to be joined together by wires, meaning we could never sit more than a few meters away from the screen.

Bluetooth offers many advantages, but there are drawbacks, too. We have to charge (充电) Bluetooth devices more often because Bluethooth shortens battery life. Besides, Bluetooth technology easily finds nearby devices so hackers (黑客) can see which devices are nearby and attack them, especially in public places like airports, trains and cafes. What’s more, most Bluetooth devices must be within about 10 meters of each other and has slow data speed.