Most of us spend all day at school or work. After a long and busy day, we want to return to a comfortable home. Smart technology（科技）can turn any home into a nicer place to live.

Smart homes have been around for some time. The Scottish company Pico Electronics invented a type of technology called X10. With X10,   household devices（设备）, such as lights and alarms, can communicate with each other by using radio waves.

Of course, 5G networks have made smart homes much more wonderful than X10. Perhaps the most widely used smart home technology is the voice-activated assistant（语音激活助手）. Google Home and Amazon Alexa allow users to interact（互动）with nearly any device in their home simply by saying a few words. This is good for children and disabled people, as they can do things that would normally be too difficult, according to How-To Geek.

Common household devices can become “smart” as well. For example, according to HowStuffWorks, a smart trash bin can keep track of the things you’ve thrown away and place an online order for new items. Smart fridges can make dinner recipes（食谱）based on the food inside.

But it’s not just about convenience. Smart homes are also good for the environment. By turning off devices that you’re not using, smart homes can lower electricity（电）you use. Using less energy means that we use fewer natural resources（资源）, which is good for the environment.

Chang’e 5 completed its task successfully in 23 days, not only did it return with valuable rock and soil samples from the moon, but also brought back a group of seeds that traveled the furthest in China. More than 30 kinds of seeds, including that of rice, oats etc., were placed inside the Chang’e 5 spacecraft and went around the moon for about 15 days.

Scientists wished to check what would happen to the seeds after the task. This task offered good opportunities to scientists, which helped them to deepen their studies on the effect of cosmic rays (宇宙射线) on the growth and development of life on Earth.

Space-based mutation breeding (太空诱变育种) refers to the process of placing seeds in the environment such as microgravity (微重力), vacuums (真空) and cosmic radiation (宇宙辐射) during a spaceflight and then sending them back to Earth for further study and planting. Scientists study and examine several generations of plants grown from seeds which went into the space and study their changes-some are desirable while others are bad and negative. Those with good changes will be kept for further research, and will be introduced to farmers after getting permission.

Space breeding (育种) can make the seeds change faster than the experiments on the earth and can bring about some wonderful results. Compared with the traditional methods, space-developed methods can make the seeds grow much better, such as having shorter growth periods and having more power to fight against diseases and insect.

China did its first space breeding experiment in 1987, using a satellite to carry seeds into space. Since then, hundreds of kinds of seeds and seedlings have traveled with dozens of Chinese spaceships. Space breeding has helped to produce more than 200 new types of mutated plants in China that have been allowed to be planted across the country from grains to vegetables and fruits.

The Chang’e 5 brought back 1, 731 grams of moon’s rock and soil to Earth, showing a historic achievement 44 years after the last moon’s rock and soil were taken back.

China’s virtual (虚拟的) human industry is developing rapidly in recent years. Although the virtual humans not real, they serve in different fields in today’s society, including education, entertainment and business.

On October 14th, 2022, China Daily released a video of its digital employee (员工) Yuanxi. In the video, this young and active virtual girl invited people to explore the rock art with a history of 9,000 years. In a dress of Chinese style, she introduced the old stone carvings of the Helan Mountains in Ningxia. Later, she showed up again on the website, inviting people to join her journey back in time to 3 ,000-plus years ago and look for the source of Chinese characters.

Throughout the Beijing 2022 Winter Olympics, China’s first AI sign language host served deaf people around the clock. The virtual host was produced by Xiling platform, which was built by a Chinese technology company. The platform provides a complete set of services for the creation and operation of virtual humans in various fields such as television and the Internet. It has also worked in cooperation with Shanghai Pudong Development Bank, China Everbright Bank and China Unicom to launch a digital human to improve working efficiency and reduce Labor costs.

The total size of China’s virtual human market is expected to reach 270 billion yuan by 2030, according to an industry report.

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