The government in China ended his one-child policy and let families have two children instead in 2015.

    A Chinese Communist Party statement gave a number of reasons for the change in policy. The statement said the change is meant to balance population development, stop a falling birth rate(出生率)and strengthen the country's labor force(劳动力). China, with the largest population in the world, started the one-child policy in 1980. But the government allowed only a small number of couples to have two children. For example, some families in the countryside could have two children, if the first-born is a girl.

    In 2013, the Chinese government gave other couples a chance to have two children if one of them was an only child.

Jiang Quanbao, a teacher and population expert, explained how Chinese families react(反应) to the newest policy. "Too many young people in the cities are no longer interested in having a second child," he said. "People in the countryside are more interested. But some of them are already allowed to have two children." At the end of 2014, China had a population of 1.37 billion people. A total of 800 million of them have jobs. But the labor market need of labor by the year 2050. With the two-child policy, an increase in births can solve this problem.

    Boys and girls, what do you think of the two-child policy? Do you want to have a new-born brother or sister?

    In recent years, there have been many breakthroughs in the AI (人工智能) field. Here, let us see four of the most interesting developments in AI in 2017.

    If you travel by air across the center of Africa or South America, you fly over forests for thousands of kilometres．These great forests are the seas of trees．They are full of thousands and thousands of different kinds of plants and animals．However, the world's forests are getting smaller all the time．We are cutting down the trees because we need wood, and we need more farmland as well．Some people say that there will not be any forests like these left in 20 to 30 years．What will happen if they disappear? If we cut down our forests, a lot of plants and animals will disappear from the world, in a lot of places the new farmland will soon look like the old deserts, for example, crops will not grow there．What's worse, it will not rain very often, and the weather will get very hot．Perhaps the climate of the world will change, which will be dangerous for everyone in the world．That is why we must take care of our forests．

    Is human blood all the same? "Sure," you may say. "It's all red." Well, it's not as simple as you might know. Blood is made up of different pans, such as red blood cells, white blood cells, and platelets (血小板). Two chemical molecules (分子) on the red blood cells make people's blood different. Scientists mark one molecule "A" and the other molecule "B".

    According to which and how many molecules are on the red blood cell, scientists divide blood into four types: A, B, AB and O. Your blood type will stay the same through your whole life. Scientists have been wondering if there are some links between people's blood type and their personalities (个性), but they don't know for sure. Some say that people with the same blood type may have things in common.

    What's your blood type? Does your friend have the same blood type as you? Read the following.

    People with type A: They look peaceful from the outside. But they ask so much of themselves that they may be very agitated inside. They become happy or sad easily. Sometimes they are shy but always very careful. They can easily win people's trust.

    People with type B: They have strong minds. Once they begin a task and make up their minds to do it, they will not give up easily. They'll try their best to finish it and do it well. They always try to make themselves different from others. They want to do things in their own way.

    People with type AB: Maybe they are the strangest among all blood types. They can be both open and shy, noisy and quiet at the same time! They are responsible and always ready to help others.

    People with type O: They're open and good at making friends. They always begin tasks but don't always finish them in the end. They have lots of new ideas and love to be the centre of attention. They always strongly believe in themselves.

    How do you light up the night sky? The answer is by using electricity. But did you know that nature can glow (发光), too?

    Scientists have found many glowing living things. Most of them live in the ocean. Some use their lights to talk to each other. Others use them to hunt, to mate (交配) or to protect themselves. The vampire squid (幽灵蛸), for example, uses a cloud of light to scare enemies.

    Scientists around the world are looking at this kind of light for new ideas. In 2013, the US company Gleaux said it has created the world's first light-producing plant, the Daily Mail reported. It is a genetically-modified (转基因的) plant. It can glow like a firefly.

    Alexander Krichevsky, the company's founder (创始人), and other scientists hope that in the future, glowing plants could replace lamps and glowing trees could light up highways. Krichevsky also hopes the technology could be used in farming. Farmers could know when their crops need water or are ready to be picked if they glow.

    While Gleaux is working on glowing plants, the French company Glowee is trying to use glowing bacteria (细菌) to light up shop windows and street signs. It's the same type of bacteria that cause a type of squid to light up, New Scientist Online reported.

    "Our goal is to change the way we produce and use light," said Glowee founder Sandra Rey. "We want to help reduce the 19 percent of electricity consumption (消耗量) that is used to produce light.