Smog is a big problem in many Chinese cities. But it seems that besides wearing a mask, few of us know what has caused the smog and what to do to beat it. In fact, burning too much coal and oil are the main causes of PM2.5 and smog (雾霾).

    To solve the problem, we should clean our coal and oil or replace them with cleaner energy such as natural gas. We ordinary people can do something to help control smog, too.

    What can we do to help beat the smog?

    Choose to take public transportation. Though many people have their own cars, they had better take public transportation, such as the subway or buses. If the destination (目的地) is not far away, you can also walk ________ ride a bike.

    Call the hotline 12369. You can call the number for complaints and questions about environmental issues. It is run by China's Ministry of Environmental Protection. If you call the number, some officers can come and try to solve the issues, so please remember it.

Report and resist pollutant source. If you find any pollutant source, take a picture of it and post it on your social media accounts. Remember to add “@local environmental departments” on weibo. Payattention to factories that pollute the environment and don't buy products from them.

    Our environment will become better if everyone is concerned (关注) with the environment. This is what we need in the future. So everyone can do something to beat smog.

Hurricanes(飓风) are storms. They can cause terrible waves, wind and rain. They happen in the Atlantic Ocean and the Pacific Ocean most of the time.

Category(类别)

·Scientists divide(划分) them into five categories according to the wind speed.

·A Category 5 hurricane can destroy(摧毁) all the buildings.

Characteristic(特征)

·Hurricane Season usually comes on June 1^st and ends on November 30^th in the Atlantic Ocean, from May 15^th to November 30^th in the Pacific Ocean.

Danger

·It can cause flood when a hurricane comes with heavy rain.

·A hurricane has an eye. The eye means the center of a hurricane. After the eye passes, the wind and rain comes again.

Safety advice

·Stay inside during the Hurricane, or you'll be injured.

    The expression "lanshouxianggu" has been quite popular on Chinese social networking sites. You may have used it many times when chatting online. However, did you know that the "blue thin mushroom" was not just magic of Photoshop and was really there in nature?

    Well, let' s meet Entoloma hochstetteri (霍氏粉褶菌).This is a kind of naturally-blue fungus(真菌) The plant looks very small. Its sten' s diameter(梗的直径) measures only about 5 millimeters. Entoloma hochstetteri can be found widely in New Zealand, especially on the west coast. The Maori name for it is "werewere-kokako." It seems New zealand is very proud of producing this unusual species-the country prints the blue mushroom on its $50 notes.

    Athough the species is very unusual, little is known about it. Silas villas-boas is a scientist at the University of Auckland. He said he was very disappointed that nobody had ever tried to test the blue mushroom in the lab, "You can even count the number of scientific articles on it on one hand, he said. The scientist decided to be the first to study the plant. A group of researchers have been helping him with the study.

    In an early test, the researchers found alkaloids(生物碱) and Omega-3 fatty acids(w-3脂肪酸)in the blue mushroom. While the acids are helpful to health, alkaloids soetimes influence how the brain works. However, Villas-Boas said the substance was very common in plants. So far, the researchers have not found any toxins(毒素) in Entoloma hochstetteri, but they are not yet sure if it can be eaten. Villas-Boas said more testing would be required.

    Is there intelligent（有智力的）life on other planets? For years, scientists said "no." or "we don't know." But today this is changing. Seth Shostak and Alexandra Barnett are astronomers（天文学家）. They believe intelligent life exists（存在）somewhere in the universe. They also think we will soon contact them.

    Why do Shostak and Barnett think intelligent life exists on other planets? The first reason is time. Scientists believe the universe is about 12 billion years old. "This is long enough for other planets to have intelligent life, "say Shostak and Barnett. The second reason is size the universe is huge. "Tools like the Hubble Telescope（哈勃望远镜）have shown that there are at least 100 billion galaxies, "says Shostak. "And our galaxy, the Milky Way, has at least 100 billion stars. Some planets going around these stars might be similar to the earth. "

    In the past, it was hard to look for signs of intelligent life in the universe. But now, powerful telescopes（高倍望远镜）allow scientists to discover smaller planets-the size of Mars or the earth-in other solar systems, these planets might have intelligent life.

    Have beings from space already visited the earth? "Probably not, "says Shostak. "It's a long way away. However, intelligent beings may contact us in other way, such as radio signals（信号）. In fact, they may be trying to communicate with us now, but we don't have the right tools to receive their messages. However, this is changing. By 2025, we could make contact with other life forms in our universe and we might help each other. "

    When he was nine years old, an American boy called Milo Cress had a question: How many plastic straws (吸管)do Americans use every day?

    He quickly learned there wasn't a simple answer. The boy tried to find it out himself. Through lots of research, Cress found out that Americans use about 500 million straws every day. In hopes of cutting down plastic waste, he founded the Be Straw Free project in 2011.

    Cress started the project in his hometown Burlington. Vermont. He asked a local restaurant to stop offering straws with every drink order. It was a simple change. However, it would save money. And by doing that, the restaurant would cut down on its straw use by 50 percent.

    For the year that followed, Cress tried to spread his project across the United States. More and more restaurants agreed to join. They stop providing the customer with a straw unless he or she asks for one. Last April, Seattle became the first American city to completely ban plastic straws.

    After his project became popular, Cress took his findings on the road. He has spoken to tens of thousands of students around the world. He wants to encourage more people to say no to plastic straws.

    "Focusing on straws is one simple step we all could take," Cress says. "And it makes me feel that I, as a kid, could make a difference, too."