Experiments under way in several labs aim to create beneficial types of genetically modified foods, including starchier potatoes and caffeine-free coffee beans. Genetic engineers are even trying to transfer genes from a cold-winter fish to make a frost-resistant tomato.

    A low-sugar GM strawberry now in the works might one day allow people with health problems such as diabetes (糖尿病) to enjoy the little delicious red fruits again. GM beans and grains rich in protein(蛋白质) might help people at risk of developing kwashiorkor. Kwashiorkor, a disease caused by severe lack of protein, is common in parts of the world where there are severe food shortages.

    Commenting on GM foods, Jonathon Jones, a British researcher, said: "The future benefits will be enormous（巨大的）, and the best is yet to come". To some people, GM foods are no different from unmodified foods. "A tomato is a tomato," said Brian Sansoni, an American food manufacturer.

    Critics of GM foods challenge Sansoni's opinion. They worry about the harm that GM crops might do to people, other animals, and plants.

    In a recent lab study conducted at Cornell University, scientists tested pollen(花粉) made by BT corn, which makes up one-fourth of the U.S. corn crop. The scientist dropped the pollen onto milkweed, a plant that is the only known food source of a butterfly caterpillar(毛虫). Within four days of feeding on the leaves, almost half of a test group of caterpillars died. "This is a warning bell." said Cornell researcher Linda Raynor.

    Some insects that are not killed by GM foods might find themselves made stronger. How so? The insecticides are used on the crops to kill the pests. But GM plants produce a continuous level of insecticide. Insects relying on those crops may develop resistance to the plants and they may also develop a resistance to the insecticide.

    At the forum on GM food held last year in Canada. GM crops that have been made resistant to the herbicide might crossbreed with wild plants, creating "superweeds" that could take over whole fields.

    So where do you stand? Should GM food be banned in the United States, as they are in parts of Europe? Or do their benefits outweigh（胜过） any of the risks they might carry?

     If you want to visit only the sights that you think are most interesting, you should definitely book one of the many private tours in NYC.

Landmark Private New York Tours

     The best way to make the most of your visit to the top NYC landmarks is to use one of the private tours in NYC.

     NY See It All: From traveling through Manhattan to getting onto a boat to visit Ellis Island and the Statue of Liberty, this private NYC tour delivers superiors service. Customize（定制） your stops and see why this tour is one of the best private tours in NYC.

     NY Limo Tour: After choosing what you want to see, this private tour in NYC lets you write the route of your day. Whether you want to see historical NYC sights, movie sights, or cultural sights, it will help make your visit memorable.

     Aerial Landmark Tour: This is a fun and exciting way to explore New York City. On this 20-minute helicopter tour, you'll see the very best landmarks in Manhattan and the Bronx. Family-Friendly Private New York Tours

     NYC isn't just a playground of adults; these family-friendly private New York City tours are ideal for people traveling with kids.

Revolutionary Era Walking Tour: When you book this informative NYC walking tour, you and your kids will wander around Manhattan's Financial District and hear all about the American Revolution. With knowledgeable guides, your kids will love the tour too.

     Kids Greenwich Village Tour: This fun NYC walking tour is specifically created for children. You and your kids will visit some famous Greenwich Village sights, while the children, led by friendly guides, play games that relate to math, science, foreign language, and the arts.

TaIL Spin

    Two dolphins race around in a big pool in the Ocean Park. The smaller dolphin Grace, shown off a few of her tricks, turning around and waving hello to the crowd. The most amazing thing about her, however, is that she's even swimming at all. She doesn't have a tail.

Grace lost her tail as a baby when she got caught up in a fish trap. When the dolphin arrived at the Ocean Park in December 2005, she was fighting for her life. “Is she going to make it?” Her trainer, Abbey Stone, feared the worst. Grace did make it — but her tail didn't. She ended up losing her flukes and the lower part of her peduncle.

Over the past six years, she has learned to swim without her tail. Dolphins swim by moving their flukes and peduncle up and down. Grace taught herself to move another way—like a fish! She pushed herself forward through the water by moving her peduncles from side to side.

    The movement put harmful pressure on Grace's backbone. So a company offered to create a man-made tail for her. The tail had to be strong enough to stay on Grace as she swam but soft enough that it wouldn't hurt her.

    The first time Grace wore the artificial tail. She soon shook it off and let it sink in the bottom of the pool. Now, she is still learning to use the tail. Some days she wears it for an hour at a time, others not at all. “The tail isn't

necessary for her to feel comfortable,” says Stone, “but it helps to keep that range of motion(动作) and build muscles(肌肉).”

    Now, the dolphin is about to get an even happier ending. This month, Grace will star in Dolphin Tale, a film that focus on her rescue and recovery. Her progress has inspired more than just a new movie. Many people travel from near and far to meet her. Seeing Grace swim with her man-made tail gives people so much courage.

    Summer holidays are coming. Here are two posters for members of English Club in the  schoolyard：

    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's 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.

Charles Darwin was a very famous scientist who lived in the 1800s.His ideas about evolution completely changed the way scientists understand the natural world.He recorded his ideas in notebooks marked with letters of the alphabet(字母表),which have been considered extremely important for showing how he developed the evolution.

The Cambridge University Library had several of Mr.Darwin's notebooks.The two that were missing were kept in a small box,and were last seen in 2000.In 2001,someone noticed that the box was missing.Luckily,the library had taken pictures of the notebooks' pages,so the information wasn't completely lost.

In 2020,the library made a huge effort to find the books.Workers searched through the 10 million books and other things in the library,but they didn't find the notebooks.Finally,the library asked people around the world to help look for the books.They officially reported the missing notebooks as stolen so that the police around the world would search for them.

Nobody could ever have expected the way in which the notebooks were returned recently:in a pink gift bag with a note that said "Librarian,Happy Easter,X".People at the library quickly recognized the blue box that the notebooks had been stored in.Inside a brown envelope they found the two missing notebooks,tightly wrapped in plastic.After the police had examined the package,library workers were able to open and carefully study the notebooks.They were pleased to learn that the notebooks were in good shape.They hadn't been damaged and they weren't missing any pages.

The timing of the return is perfect.The library was planning a show called "Darwin in Conversation",which is set to open in July.Now the missing notebooks can be part of that show.