Science is proving what pet owners have long believed: Dogs understand what we're feeling. Especially, dogs can recognize(识别) the difference between a happy and an angry human face, a study published Thursday in Current Biology suggests.

    It's the first research to show that dogs are sensitive (敏感) to our facial expressions, says the author Ludwig Huber at the University of Veterinary Medicine, Vienna.

    In the Austrian study, 20 different kinds of pet dogs were taught to play a computer game through a series of exercises. In the first step, the dogs were shown two touch screens, one with a circle and one with a square. Through the exercises, they learned that a treat would appear if they chose the right one.

    Eleven of the 20 dogs were able to catch on to rules of the game and make it to the next test, where they were shown photos of happy and angry faces. The dogs were rewarded if they picked certain expression correctly. During the test, the dogs were shown only the upper half or the lower half of a face.

    It was easier to teach the dogs to choose a happy expression than an angry one, suggesting the dogs do indeed understand the meaning behind the expression, Huber says.

    As a test, the dogs were then presented with: the same half of the faces they saw during the training, but from different people， the other half of the faces used in training， the other half of new faces， the left half of the faces used in training.

    In the cases, the dogs chose the right answer 70 to 100 percent of the time.

    Dogs who had been trained to recognize an expression of anger or happiness on the upper part of a face could find the same expression when shown only the lower part. Huber says, "The only possible explanation is that they recall from memory of everyday life how a whole human face looks when happy or angry."

    Dog owners know their pets not only recognize emotions but also understand the feelings.

    Many environmental groups are warning that oceans of the world are in great danger. In the past 50 years, the number of water with zero oxygen(氧气) in the open ocean has increased more than four times. In the near coast water bodies, including the river mouth and seas, low-oxygen areas have increased more than 10 times since 1950.Scientists discover that oxygen continues dropping ever outside these zones as the Earth warms. To stop the drop, the world needs to control in both climate change and nutrient(养分) pollution.

    Oxygen is a must to life in the oceans. The drop in ocean oxygen is among the most serious effects of human activities on the Earth's environment.

    This is the first time for the scientists to take such a deep look at the causes, results and solutions to low oxygen worldwide, in both the open ocean and the near coast waters. About half of the oxygen on Earth comes from the ocean. However, mixed effects of nutrient loading and climate change are greatly increasing the number and size of "dead zones" in the open ocean and the near coast waters, where oxygen is too low to support most sea life.

    In the areas traditionally called "dead zones", like those in Chesapeake Bay and the Gulf of Mexico, oxygen drops to levels so low that many animals have trouble in breathing and die. As fishes run away from these zones, their living areas become smaller and smaller. But the problem goes far beyond "dead zones". Even smaller oxygen drops can hold up the growth in animals and lead to disease or even death. Low oxygen also can cause the release of dangerous chemicals. Although a few animals can grow well in dead zones, overall biodiversity(多样性)falls.

On social media platforms such as Xiaohongshu, we're seeing more posts with the tag lines "I will listen" and "listen to me." A puzzled person may have trouble deciding on where to go on a vacation, which restaurant offers the best seafood or whether Huawei's Mate 60 is a better buy than the iPhone 15. Write a post titled "I will listen" and it's likely that a warm-hearted person will quickly reply with a suggestion.

Now, the problem is, should you follow the advice of a complete stranger? Is his or her advice true or is it just a personal opinion? Opinions, after all, are not facts－they are just personal judgments. Still, it's important to take different voices into consideration.

Whenever I buy something online, I always read the comments ( 评 论 ) posted by the last customers. If there are too many negative comments, I probably won't consider buying it. On the other hand, if all of the comments are unusually positive, my doubtful brain takes over and I think the seller may be using comments to increase the sale of the product.

Apart from online business posts, other "listen-to-me" posts cause a more complex problem. In these posts, people are often giving advice on traps ( 陷 阱 ) and problems that could trouble other people. Personal problems such as relationships, job choices and even mental health are among the most common topics. Their suggestions may be truthful, but they don't necessarily fit in with the special situation of others.

For these big "topics", it's better to talk to friends, families, teachers and professional experts. Those people who are close to you know and care about you and will stay by your side, unlike an online poster you may never hear from again.

The Internet is like a great "shop" for getting and exchanging information. But, as with any shop, let the buyer be more careful.

How can we practice our {#blank#}1{#/blank#}English?

The first and the most important thing is to believe {#blank#}2{#/blank#}.You should always be full of confidence，or you won't be able to improve your English.You should often encourage yourself，"Come on！Don't be afraid！"You should never lose heart and never give {#blank#}3{#/blank#}.

Maybe you are afraid of losing face，but you should think since we are students and we're {#blank#}4{#/blank#}，there's no need to worry {#blank#}5{#/blank#}anything.You must always be active in practice.It's no problem that your pronunciation and intonation (语调) can't be as good {#blank#}6{#/blank#}the native people because we are Chinese，and we don't have chances to live in {#blank#}7{#/blank#}countries and talk with the people there.But you must know that the main way to study English is to make ourselves understood and {#blank#}8{#/blank#}other people.You should believe that native speakers will not laugh at you，but {#blank#}9{#/blank#}they will encourage you.So if you {#blank#}10{#/blank#}brave enough，you'll certainly make rapid progress in your spoken English.

Don't be shy or afraid！Just have a try.

Many traditional woodcut prints （版画）are either black and white or simple in color, but reduction woodcuts （绝版木刻）can show rich colors. 

The reduction woodcut uses one piece of wood to make a {#blank#}1{#/blank#}（colour）artwork. The artist cuts and prints different layers （层）in order on the same piece of wood. The reduction woodcuts became an intangible cultural heritage （非物质文化遗产）in Pu'er, Yunnan, {#blank#}2{#/blank#}2009. 

LengGuangmian, in his {#blank#}3{#/blank#}（40）, is a reduction woodcut artist. Leng started learning it in 2003. He said that making reduction woodcut prints is just like an adventure. "Every time we cut on the wood and then print, we never know {#blank#}4{#/blank#} it will be like in the end." 

Finishing such work is not easy. He said that before cutting, he needs to plan for {#blank#}5{#/blank#} whole print and choose colors for different layers. A big print usually takes months to finish. 

Leng hopes that both woodcutting skills and the life in Pu'er{#blank#}6{#/blank#}（show）through his creative artwork. "For my works, there are two themes: Tea Horse Road （茶马古道）, because Pu'er is one of the starting places of that road; and disappearing villages," Leng said. "Many old villages in Pu'er need {#blank#}7{#/blank#}（build）again. As a result, I want to make people remember their{#blank#}8{#/blank#}（beautiful）before they are gone." 

LengGuangmian is now getting more people {#blank#}9{#/blank#}（know）about the reduction woodcut. He and brings the art into schools in Pu'er. To make students understand the art better and learn it more quickly, he even thought of a new idea of cardboard printing. "By using a smaller cardboard and making it {#blank#}10{#/blank#}（simple）with three to five colors, students can get the charm of the art," Leng said. 

Nowadays, the popularity of Chinese traditional works of art is increasing. At an art museum in Nanjing, capital of Jiangsu Province, the woodcut prints are taking center stage for the first time. 

The top﹣selling album（唱片），Songs of the Humpback Whale，was made public in 1970. This collection of nature recordings changed the way many people thought about whales，and it helped save thousands of wha les. 

The album might never have been made without a sound engineer named Frank Watlington. In the 1960s，Watlington was making underwater recordings when he noticed some strange，deep sounds. He realized they were coming from whales. Watlington played the recordings for a pair of scientists named Roger Payne and Katy Payne. When they listened，they fell in love with these beautiful voices at once. 

Katy Payne studied music as well as animals，and she was greatly surprised by how the whales communicated using sounds like an opera singer. She also noticed another interesting fact：the sounds had clear patterns. According to scientists，an animal sound with a repeating pattern is called a song. Some scientists even compared these singing animals to musicians. 

The Paynes thought that other people should also hear the beauty of the whales' songs. So Roger made the recordings into an album. The time when the album came out，whales were often caught，killed and traded for money. Some kinds were even in danger of dying out. Most people had never thought that whales could communicate through songs. But after hearing the album，they began to think differently. 

The album led people to take action to save whales. Musicians began using whale songs in their music，and whales were included in movies and television shows. In 1982，a ban to stop deep﹣sea whaling was made. Before it，in the 1950s and 1960s，more than fifty thousand whales per year were killed. After it，the number went down below two thousand. 

It might seem impossible that just one album could help save the lives of so many whales. But this album told people secrets about whales that had long been hidden under the sea. It allowed whales to finally share their songs with the human world.