Dear SJ,

    Losing a best friend is never easy.

    Your problem, is not just that you miss your best friend, it is that you feel empty and lost without her friendship.

    It takes time to get over a lost, and during that time, your mind is getting used to a new way of being. This is usually a good thing, even if it feels like a bad thing.

    Now that you are on your own, you are being forced to learn to be by yourself and to rely upon your own inner voice for guidance. I am sure that this feels strange for you, but if you can hang on for a bit longer, it may work to your advantage.

    Best friends are cool, but it is important to know the difference between missing someone and being too independent upon them.

    At your age, girls do tend to stick together and having a good boyfriend may not yet be the better choice. Your friend is leaving you, her best friend, for a boyfriend. Boyfriends are completely different from best friends. The distinction is that boyfriends come and go, while girl friends often stay in your life throughout high school, and even afterwards. It is a completely different sort of bond.

    I suggest that you take advantage of this period in your life to expand your horizons. Enjoy the freedom of having no best friend for a while, and hang with the group. By the time your former best friend breaks up with her boyfriend, you will be in a completely different place, a far better place.

    And, by the way, next time you feel empty and lost, try to write about it in a diary. In several months, you will look back and read it with curiosity about yourself. “Who was I then, and what could I have been thinking?”

    Some people like modem art, while others say that is rubbish. But a cleaner who works in the Tate Gallery in London isn't able to tell the difference. The woman, whose name isn't known, mistook a work of art by the German painter Gustav Metzger for a bag of rubbish, and threw it out with other bags. The plastic bag, which contained pieces of paper and cardboard, was later recovered outside the gallery, but the artist thought that it was too damaged to be put on show again. 78-year-old Mr Metzger explained that the exhibit, which he said was a copy of a similar work he had created in 1960, was meant to show that all art is temporary and “finite” (有限的).

    Embarrassed officials at the museum said that they had to call a meeting with cleaners to explain which things should not be touched. They would not say whether Mr Metzger would be paid any compensation for the incident. However, to make absolutely sure the same thing would not happen again, they decided to cover Mr Metzger's work every evening with a colored cloth. In this way the cleaners arriving after the gallery had closed to the general public would realize they should not touch it.

    This is not the first time that museum cleaners have had trouble distinguishing exhibits from rubbish. In 2001, in another London gallery, a cleaner threw away a work by the well-known British artist Damien Hirst. It was an arrangement of empty beer bottles, coffee cups, and overflowing ashtrays, which were meant to indicate the chaos in the life of an artist.

    However, cleaners don't always throw things away—sometimes they clean them! This was the case with a dirty bath, which was on show in a gallery in Germany. Without asking what the bath was doing in the gallery, the cleaners simply scrubbed it clean.

    It's been a hard time for rhinos (犀牛) lately. Recently the International Union for Conservation announced the western black rhinos had died out in the wild. It was last seen in western Africa in 2006. Now, those who work to protect the animals are trying to make sure that won't happen to other rhinos.

    19 south-central black rhinos in South Africa were driven to an area nearly 1,000 miles away, which was said to be the gentlest and quickest way to transport the animals. They were taken to a new home that would keep them safe from hunters.

    Though it is not allowed to hunt rhinos, many are still killed for their horns, which can sell for as much as $ 30,000 each. Most of them are used to make drugs as traditional medicines in Asian countries. Some people believe that the horns work well in treating pain, fever and even cancer. However, there is no medical evidence yet.

    Black rhino population began falling rapidly in the second half of the 1900s because of poaching. In fact, some people still hunt the animals at the risk of being put into prison. And many of the places where the animals used to live in were destroyed when people started building farms on the grasslands. Until the 1960s, about 65,000 black rhinos lived throughout most of Africa. Today, fewer than 5,000 are left—most of them in zoos and wildlife reserves.

    South Africa has the largest population of rhinos in the world. Poaching is an especially big problem in that country. So far, more than 340 rhinos have been killed there. Since 2003, the Black Rhino Expansion Project has been helping the south-central black rhinos in South Africa. The group works with landowners to find areas where rhinos can live safely away from hunters.

    So far, the group has successfully saved about 120 rhinos. Leaders of the project say the south-central black rhinos have seen a rise in numbers. It is hoped that, with continued support, these rhinos can escape the unfortunate result of the western black rhinos.

    When Boris left school, he could not find a job. He tried hard and he wrote letters to many companies until he could not afford to buy any more stamps. Boris began to lose his confidence, then depressed. Still he went on trying and still he failed. He began to think that he had no future at all.

    "Why don't you start your own business?" one of his uncles told him. "The world is a money­locker. You'd better find a way of opening it."

    "But what can I do?"

    "Get out and have a look round." advised his uncle. "See what people want; then give it to them, and they will pay for it."

    Boris began to cycle around the town and found a suitable piece of waste ground in the end. Then he set up his business as a cycle repairer. He worked hard, made friends with his customers and gradually managed to win his good fame. A few months later, he found that he had more work than he could deal with by himself. He found a number of empty shops but they were all no good: in the wrong position, too expensive or with some other problems. But at long last, he managed to find an empty shop in a new place where there were plenty of customers but no competition.

    Boris and his assistant taught themselves how to repair motor­cycles. Slowly but surely the profits increased and the business developed. At last, Boris had managed to open the money­locker and found bank notes and gold coins inside.

    A dog spent the last four years of his life waiting a crossroad in the Thai city of Khon Kaen as if waiting for someone. People originally thought the dog had been abandoned, but then realized that he looked healthy, so people asked around about him. It turned out that the dog had indeed been spending most of his time around that crossroad, but a woman had been coming -.round regularly to bring him food and water.

    One day, while photographing the dog everyone called Leo, a reporter met the woman who had been taking care of him. She had come to drop off some food. After learning the story about the dog and the woman, the reporter decided to share the story on social media. The post soon went viral and the photos of Leo got shared hundreds of times. And the photos reached the eyes of Leo^ former old owner.

    Nang Noi Sittisarn, a 64-year-old woman from Thailand's Roi Et Province, almost had a heart attack when her daughter showed her a photo of the beloved dog named BonBon she had lost during a car trip. When she learned that he had been waiting for her in the same spot for the last four years，her heart melted(融化).

    Auntie Noi told her daughter to drive her to where the dog was waiting. When she got there and called his name. BonBon, the poor dog started wiggling(扭动)his tail and came to her，but when she tried to take him home with her, he was unwilling to follow. She didn't want to force the dog to come with her so she agreed to leave him with his new master. However, she and her daughter will come to visit him regularly.

A lunar crystal (水晶) was found in lunar basalt particles (玄武岩颗粒) collected from the moon in 2020 when the Chinese moon mission landed in Oceanus Procellarum, returning with more than 1.7 kg of lunar samples delivered safely to the Earth. 

The crystal found on the near side of the moon is giving scientists hope of providing limitless power for the world forever. It is made of material previously unknown to the scientific community and contains a key ingredient for the nuclear fusion (核聚变) process, a form of power generation that uses the same forces that fuel the sun and other stars. It is transparent and roughly the width of a single human hair, and it formed in a region of the moon where volcanoes were active around 1.2 billion years ago. 

One of the primary ingredients found in this crystal is helium-3 (氦-3) , which scientists believe may provide a stable fuel source for nuclear fusion reactors. The element is incredibly rare on the Earth, but it seems to be fairly common on the moon. China's next moon mission is expected to be carried out by Chang'e 6 in 2024, which will attempt to collect the first samples from the far side of the moon, which never faces the Earth. 

Although it is too early for scientists to have made financial estimates on such a fuel source, it will undoubtedly be extremely costly. There is, of course, the matter of bringing the crystals back from the moon, especially in large amounts that are needed to fuel fusion reactors. 

Helium-3 produces significantly less radiation and nuclear waste than other elements. The current nuclear fusion process has raised serious safety concerns, and as a result, scientists have been searching for a way to create nuclear power from nuclear fusion. During the fusion process, radioactive waste is not produced, potentially making a securer and more efficient fuel source. 

Around 25 tons of helium-3 could power the US for a year. Multiple private companies and countries with space agencies have signaled their intentions to mine the moon for helium-3, and this latest discovery could kick start the race.