From the loss of wildlife to rising sea levels, we're all well aware of the problems that climate change could cause.

    But while it may seem like such issues won't affect most of us directly，it looks like future generations could grow up without something that many of us now take for granted: chocolate.

    According to an essay published by the US National Oceanic and Atmospheric Administration, changes to the climate in the regions that produce cacao - the plant from which chocolate is produced - may mean that it will soon become extinct.

    Most of the world's cacao grows in countries close to the equator，with over half of it growing in the African nations of Ghana and Ivory Coast.

It's predicted that by 2050, climate change will have accelerated the rate at which temperatures in these countries rise, making it extremely difficult for cacao to grow there.

    The problem doesn't lie in increased heat, however，but in lower humidity (湿度)，as it's believed that rainfall will stay at the same level if the temperature rises.

    “In other words, as higher temperatures squeeze more water out of soil and plants, it's unlikely that rainfall will increase enough to offset the moisture (含水量) loss,” Michon Scott, the essay's author, wrote.

    To help fight this problem, researchers from Berkeley University in the US are working on changing the DNA of cacao plants to allow them to survive in dryer conditions by using gene editing technology, according to US News.

    In the meantime, US company Mars, one of the world's biggest manufacturers of chocolate products, announced in January that it would spend $1 billion to help reduce the effects of climate change.

    “This is a world issue, and it requires everyone to work together,” Mars spokesperson Barry Parkin told Business Insider.

    The message here is that if we all do our part, we may be able to prevent some of the worst impacts of climate change. Or if we're unlucky, chocolate will become a thing of the past.

    With beautiful canals, top art museums, and cycling culture I Amsterdam is one of the most popular travel destinations in the world. As the capital and most populous city in the Netherlands, it's often referred to as the “Venice of the North” because of its wide system of bridges and canals. Here are some key points for you to keep in mind while planning a trip there.

    Must-See Attractions

    Most visitors begin their Amsterdam adventure in the Old Centre, which is full of traditional architecture, shopping centers, and coffee shops. The top museums to visit are the Rijks museum, the Ann Frank House, and the Van Gogh Museum. As a World Heritage Site, the Canal Ring was originally built to attract wealthy home owners and an area for celebrity spotting and nightlife today.

    Transportation

    Travelers should be aware that Amsterdam Airport Schiphol is one of the busiest airports in the world. This airport is located about 15 kilometers southwest of the city center. You can catch a train from Schiphol to Amsterdam Central Station, which has many connecting routes. It's not a good idea to drive a car to the city center. Cycling is popular here, and it's easy to rent a cheap bike around the town. Amsterdam has a flat terrain (地形) and it's a good choice to explore the city on foot.

    Money-saving Tips

    Look for accommodations in Amsterdam's South District where rates are generally cheaper than in the city center.

    Buy train tickets at the machine instead of the counter to save a bit of money.

    Instead of hiring a tour guide, jump onto a canal boat. They're inexpensive and will give you a unique point of view of the city.

    The arts, especially music, should be part of every school's lessons at every grade level. Students would be much smarter if they had some musical experience. They could improve their classroom skills, like paying attention and following directions. People develop all these skills when they learn music. Making music also lets children use their imagination. It provides students with a chance to try out their own ideas.

    Music not only makes children better students, but also gives them something positive to do. In a music program, children can be part of a band instead of joining a gang (团伙). Parents can enjoy listening to their children's music instead of seeing them glued to a computer or TV screen. In a school band, students get to be part of a team. They can get along well with old friends and make new friends through music.

    Music builds self-confidence, too. It gives children a sense of achievement and success. Making music is something for them to be proud of, and it lets kids practice performing in front of an audience. Music gives children an opportunity for self-expression, and that helps develop their self-confidence.

    Once again, music is important because it can make children better students, give them something positive to do, and build their character. That is why music should be offered in every single grade in every school.

    Many people believe that you lose the ability to learn new languages as you get older. Language experts, however, will tell you that you're never too old to learn a new language. As you get older, it can be more difficult to learn a new language, though.

    Children and adults learn new languages in different ways. For children, language is their life. They study for thousands of hours every year, because they need to learn languages to become part of their communities. Adults, on the other hand, are already part of a language community. Learning a new language means becoming part of another language community, and adults rarely get the chance to practice as much as young children do.

    Moreover, children learning a new language are expected to make mistakes. This gives them freedom when learning to be daring and confident. Adults, however, often feel stressed to be perfect when learning a new language. This can discourage many people and make it even harder to learn a new language.

    When young children learn a new language, they come to see various languages as a "normal" part of society. This mindset helps them to learn a new language without feeling like they're doing something unusual or "too hard".

    So if you want to learn a new language, go for it! It's never too late to learn a new language. If you're older, it may take more work, but it can be done. If you're a young child, though, now is the time to step out and learn a new language!

    We now think that chocolate is sweet, but once it was bitter. We think of it as a candy, but once it was a medicine. Today, chocolate can be a hot drink, a frozen dessert, or just a snack. Sometimes it's an ingredient（构成部分）in the main course of a meal. Mexicans make a hot chocolate sauce called Mole and pour it over chicken. The Mexicans also eat chocolate with spices like chili peppers.

    Chocolate is a product of the tropical cacao tree. The beans taste so bitter that even the monkeys say "Ugh!" and run away. Workers must first dry and then roast the beans. This removes the bitter taste.

    The word "chocolate" comes from a Mayan word. The Mayas were an ancient people who once lived in Mexico. They valued the cacao tree. Some used the beans for money, while others crushed them to make a drink.

    When the Spaniards came to Mexico in the sixteenth century, they started drinking cacao, too. Because the drink was strong and bitter, they thought it was a medicine. No one had the idea of adding sugar. The Spaniards took some beans back to Europe and opened cafes. Wealthy people drank cacao and said it was good for the digestion.

    In the 1800s, the owner of a chocolate factory in England discovered that sugar removed the bitter taste of cacao. It quickly became a cheap and popular drink. Soon afterwards, a factory made the first solid block of sweetened chocolate. Later on, another factory mixed milk and chocolate together. People liked the taste of milk chocolate even better.

    Besides the chocolate candy bar, one of the most popular American snacks is the chocolate chip cookie. Favorite desserts are the chocolate cream pie and, of course, an ice cream sundae with hot fudge sauce.

    Deisha walked up and down as she waited backstage. This would be her most important piano performance yet. At ten years old, she was the youngest performer in the recital (音乐演奏会). She had practiced playing her song more than 30 times that week. When she closed her eyes at night the music played over and over again in her head.

    Now that the day had arrived. Deisha was not sure she was ready. She smoothed her hair and picked a piece of lint (绒毛) from the new dress that her mother had bought for her. She noticed that her hands were shaking. How could she play the notes of the song if her hands were shaking? She tried to concentrate on steadying (稳住) them, but they play only shook more.

    Deisha's piano teacher, Ms Neal, walked up to speak to her. "I have something for you." she said, putting a smooth black stone into Deisha's hand. "It's a special stone. There's no other one like it in the world. You've practiced so much: you don't need anything else."

    The stage lights reflected off the rock. "Thank you," Deisha said.

    When Deisha's name was called, she rubbed the stone, stepped onto the stage, and played better than ever.

    After her performance, she noticed that Ms Neal had a whole bag of black stones. "Why did you say this one was so special?" she asked. The teacher responded, "Because, like your talent, it belongs only to you."