Do you often listen to music at loud volumes (音量)? You should know that this habit is bad for your hearing. Over 1 billion young people are at risk of hearing loss (听力丧失) ,because of listening to loud noise for long periods of time. Listening to music or watching a TV show at loud volumes can harm your hearing.

The United Nations has standards for safe listening. It is not safe to listen to sounds that are louder than 85 dB (分贝) for eight hours or 100 dB for 15 minutes. The sound of a busy road is about 85 dB and the sound of a rock concert can be about 100 dB.

Loud noise is harmful to the inner ear. Most of us are bon with about 16,000 hair cells (听毛细胞) in our inner ears. These cells notice sounds. However, listening to loud noise for a long time can make these cells work too hard and cause some of them to die. This is what causes hearing loss. Once this happens, it's hard to get your hearing back.

Some people might think that their music isn't all that loud. But this can depend on where you are. For example, if you are in a noisy place like the subway, you might turn up your music too loud without realizing it. Later, when you listen to it at the same volume in a quiet place, you alight feel uncomfortable

The "safe level" for most sound is below 80 dB for up to 40 hours a week. A level of 80 dB is about equal to (相当于) the noise of a subway.

Here is some advice on safe listening. Over-the-ear headphones   (头戴式耳机) are better than in-ear ones. They do a better job of stopping outside noise, so you can listen at a lower volume. Don't listen to loud music on your headphones for a long time. Follow the 60:60 rule: listen to music at 60 percent of your headphones' maximum volume for no more than 60 minutes a day.

Do you want to improve your physics and chemistry grades? Well, maybe you should first learn something about the struggles (奋斗) of great scientists.

The American Psychological Association did an interesting study. More than 400 students from schools in New York City took part in it. The students were divided into three groups. Group 1 read a typical textbook that describes the achievements of great scientists. Group 2 read about those scientists' personal struggles. For example, as a Jew, Einstein (爱因斯坦) ran away from Nazi Germany to avoid persecution (迫害). The last group read about the scientists' intellectual struggles, such as Marie Curie's failed scientific tests. These stories about struggles also told students how the scientists dealt with these obstacles障碍) .

The students took a science exam before the study. After the six-week study, they took another. Scientists found those in Groups 2 and 3 improved their science grades. Students in Group 1 didn't see a grade increase. Some of them even had lower grades after the study.

The study was led by Xiaodong Lin-Siegler, a teacher at Columbia University. According to Xiaodong, kids often think Einstein was truly intelligent. They believe they will never match him.

Many of them fail to realize that any success requires a long journey. Along the way, there are many failures失败) .

Students who read the struggle stories more probably said that great scientists were like themselves. The "great minds" also had to overcome obstacles to achieve success.

Xiaodong says today's science textbooks fail to bring science to life. As a result, students seldom regard science as part of their everyday lives. Instead, they just see a long list of facts that they have to remember. Xiaodong thinks textbooks should include more stories about how great scientists had to struggle to succeed. And students should focus more on how these scientists dealt with the obstacles they met along the way.

Many years ago, there was a Greek king named Midas. King Midas loved gold very much. He had more gold than any other king in the world , but he still wanted more.

One day, a beautiful fairy (仙子) came to his palace. "Midas, you are the
25． man in the world," said the fairy. "Yes," said the king, "but I want more gold because gold is the most wonderful thing in the world!" "Your wish will
26．, " said the fairy. "From tomorrow morning, you can turn everything you touch into gold."

King Midas got up very early the next morning. He wanted to see if his wish had really come true. He touched his bed with his
27． and the bed was turned into gold. The king was wild with joy. He ran around his palace and touched everything he saw. Everything was turned into gold!

The king felt hungry after running around for a long time. He decided to have his breakfast. However,
28． he touched a bowl of milk, the bowl, together with the milk in it, was turned  into gold. What's more, the bread and the meat were also turned into gold when he touched them. In the end, the poor king ate
29．.

King Midas was sitting hungrily at the dinner table when his little daughter ran to him. He hugged her and the little gal became a gold statue (雕塑)
30．. The king felt afraid. "Fairy," he shouted, "take away this
31． gift! Give me back my little gal!"

In a moment, the fairy was standing before him. "Do you still think that gold is the greatest thing in the world?" asked the fairy "No, no!" cried the king. "I have learned my lesson!" "Very well," said the fairy. "There is a spring像) in the garden. Sprinkle (洒) things that you have touched
32． the water from the spring."

The king
33． to the spring. He ran back with a bottle of water and sprinkled the water on his
34．head. Soon, the little girl came to life. He then sprinkled his breakfast. To his great joy, it turned back to real bread and meat!

We have found plastic in the ocean and in animals like birds, fish and whales. But for the first time, scientists have found plastic in human poop (大便) , USA Today reported. The findings came from a study led by scientists from Environment Agency Austria
35． The volunteers wrote down what they ate for a week and then provided a stool sample (大便样本) for testing.

36．About 20 small plastic particles (IM) were found in every 10 grams (克) of stool. "The smallest plastic particles can enter the blood, the lymphatic system, and may even reach the liver (肝脏)," said Philipp Schwabl, who took part in the research.
37．They’re not sure how the plastic got in the volunteers' bodies, either. But most of the volunteers said they drank from plastic bottles and also ate seafood that could include plastic from ocean pollution.

In fact, plastic is everywhere around us. Every year, lots of plastic waste goes into the ocean.
38． Most of the particles stay in the ocean. Others can spread into the soil. and air. Could plastic in the air fall onto food and get into the human body?

Some past studies may also give us a clue.
39．And even some drinking water has been found to have tiny plastic particles in it.

A bus ran off a bridge into the Yangtze River in Chongqing on October 28, 2018. The accident
48． (cause) by a fight between the driver and a passenger, killing all 15 people on the bus.

ccording to the police report, a 45-year-old female passenger, surnamed Liu, argued with the driver, surnamed Ran. Liu was angry because Ran refused
49． (stop) the bus after she missed her station. She then hit the driver, causing the accident. The video shows that Liu hit Ran with her mobile phone twice while Ran
50．(drive) the bus. Rather than stop in the middle of the road,. Ran kept driving. But in protecting himself, he lost control of the bus and a tragedy (悲剧) happened.

The police said that both Liu and Ran had broken criminal law by seriously endangering (危及) public safety. And the police
51． (announce), "Liu hit the driver with her phone and prevented the driver from driving the bus safely. The driver, too, didn't do his best to make sure that his driving was safe."

The accident also caused heated discussions on the Internet. Besides feeling terribly sorry for the tragedy, most Internet users blamed (指责) Liu, while some others criticized the driver. More users were talking about what they should do. One Weibo user said, "We
52． (stand) up and stop such fights between passengers and drivers
53． (avoid) this kind of tragedy."

Another user advised that a safety barrier (屏障) should be set up on the bus. It can stop passengers from
54． (touch) the bus driver.

The population of the world continues to increase, but in some areas the population is falling.

This is true in Europe and especially in Eastern Europe. In Russia, the population is going down by about 100 people EVERY HOUR! Russia's population could fall by ONE THIRD by the year 2050! And in Poland (波兰) the population is also going down because people are leaving to work in other countries.

One of the main reasons is a change of lifestyle. All over Europe people, especially educated women, have a different attitude(态度) to children than their parents. "I have one child and she is enough for me," said Galina Tereschkova, a doctor from Moscow. "My husband and I both work full-time. We can't imagine having more than one child." Many women decide to have children later in life or not to have children at all. "I don't want to have any children until I have worked for at least 10 years," said 19-year-old student Hana Markova from Prague. Her opinion is typical of 18-24 year old women everywhere in Europe.

In Poland, the population is going down for a different reason. A lot of people, usually aged between 20 and 30, are leaving the country to work abroad. Poland joined the European Union in 2005 and since then more than half a million people have moved to Britain, Germany, Spain and Italy. Even so, the population of those four countries and many other countries in West Europe is also going down.

Many governments are now encouraging people to have larger families. In France, women now receive nearly $1,000 a month for a year if they have a third child. Austrian women receive $700 a month for three years when they have their first child.