There are many dangerous sea creatures in the world. The following are some examples.

    The needlefish are commonly seen living near the surface of tropical (热带的) waters. But they can also break cover the water，and once in the air they can become dangerous flying swords. Though it is rare，people have been seriously hurt and even killed by the fish．Night fishermen in small boats are at particular risk because their lights may attract the fish.

    Saltwater crocodiles are the world's largest crocodiles，sometimes reaching 23 feet in length and topping 2，200 pounds. Yet these crocodiles hunt quietly，lying in wait below shoreline waters to attack turtles and thirsty animals that have come to drink. Saltwater crocodiles kill a number of people each year.

    There is no doubt that the great white shark sits atop the ocean food chain. The world's largest fish can weigh at over 5，000 pounds and reach lengths of more than 20 feet. Great white sharks have about 3，000 teeth，which they typically sink into sea lions，seals，and sea turtles. These sharks are responsible for a third to a half of the 100 shark attacks on humans every year.

    The sea anemone (海葵) may look like the beautiful flower for which it's named，but fish that swim too close may regret it. The sea anemone，which lives on the sea floor，uses its poisonous tentacles (触须) to stab passing creatures with a kind of poison—making them helpless and fit to be eaten.

    The surgeonfish (刺尾鱼) is an attractive reef fish that is poisonous. Scientists believe that the world's seas hold some 1, 200 different surgeonfish species and think that they injure about

    50，000 people per year. But the surgeonfish poison can also bring great benefit—they are useful in the development of new drugs.

    Listed below are the stories of women you may not know about, but definitely should.

    Hedy Lamarr

    Hedy Lamarr starred in many films. But her film career is far from her only noteworthy achievement; she was also a brilliant inventor. In 1942, she and composer George Antheil received a patent（专利）for a device that could change radio signal frequencies. The purpose of the technology was to keep military enemies from figuring out messages. But it did more than that - it laid a foundation for the wireless technology we use today.

    Maria Sibylla Merian

    Today, children can happily explain how a caterpillar（毛虫） tums into a butterfly. But there was a time when no one knew this. Until the 1670s, scientists thought that caterpillars and butterflies were two totally different creatures. Thanks to Maria, we know the truth about these beautiful winged insects. Fascinated by insects, she began collecting, studying and drawing them as a child. It was through her study of caterpillars that she discovered the truth about their life cycles. She published two volumes of naturalist research, which provide major contributions to the field of entomology（昆虫学）.

    Ada Lovelace

    Ada Lovelace, the daughter of celebrated British poet Lord Byron, wasn't a poet herself but the world's first computer programmer. We think of computers as a recent invention, but people were toying with the idea of "computing machines" in the mid – 19th century when Lovelace was alive. Lovelace's mathematical genius was apparent at a young age and caught the attention of Cambridge professor Charles Babbage, who was working to design early computing machines that would be able to quickly solve math problems. Lovelace wrote some suggestions as to how to program the machines to work out numbers.

    In addition to designing this early computer program, she was also the first to surest that these computers might be able to do more than compute. She imagined them doing almost everything, from producing images to composing music.

    A lifetime of active exercise will let you keep the body of a 20-year-old well into your 70s, scientists have found.

    The physical decline (衰退) thought to be an unavoidable part of ageing is actually the result of not exercising enough, according to the research, which found that regular cyclists kept the muscles, lungs, and even the immune system (免疫系统) of people years younger. Besides, many serious health problems could be prevented if people became more active, researchers insist.

    Janet Lord, a leading researcher, said, “Our findings prove the false belief that ageing automatically makes us weaker. We now have strong evidence that encouraging people to do regular exercise throughout their lives can solve the problem that we are living longer but not healthier.”

    She looked at 125 cyclists aged 55 to 79 who had been exercising regularly for 25 years and compared them with 75 ordinary people of a similar age and 55 people aged 20 to 36. On a series of physical measures, the cyclists showed no difference from people much younger in their immune systems and making T cells.

    Now Professor Lord aims to discover how much exercise people need to do to stay young. “You needn't work out a lot. It may be intensity (强度) that helps—like going up and down the stairs ten times a day.”

    While there is no magic method of staying mentally and physically fit in later life, the benefits of keeping active can never be ignored, whatever your age or state of health.

    It was only -28℃ when we landed in Siberia. That was cold enough to make breathing difficult. Five minutes later, I asked for a second pair of gloves and pulled my scarf tight over my nose and mouth. Clearly, I was a complete beginner to this. At the bus station, Mikhail laughed when we asked him why he wasn't freezing. He had spent the whole day outside only with his fur hat and a sheepskin coat for warmth. It was mid-afternoon and icicles（冰柱）were hanging from his beard.

    In Siberia, there's a belief that enough vodka（伏特加酒）will save you from the cold. However, it's wrong. The local hospital is crowded. Even here, icicles are hanging down on the inside of the windows, though the heating is at full power. The doctors are too busy to talk to us.

    The winter here is cruel —and this one is especially so. After her work as a teacher, Natasha Fillipova comes home. It is a freezing house. She shows us the bedroom — where ice has built up on the inside walls. One night, Natasha washed her hair before going to bed. When she woke up, it was frozen hard to the wall. Now the children are doing their homework in the bathroom — the only room warm enough to sit in. Natasha doesn't want to complain. But she is angry with the government and the architects for building terrible houses.

    The houses here are supposed to stand up to -40℃, but they don't. And her children are ill with coughs and colds. Of course, Natasha's anger is brief, and she seems embarrassed about it. According to her, Siberians are used to the cold weather. People here prefer to depend on themselves and the knowledge that spring will come in the end.

    If a person who lived 200 years ago was treated for a seizure(癫痫)today, they would be surprised by the treatment's freshness. That's because doctors in the 1800s were influenced more by original medical beliefs than science.

    Rather than thinking the brain caused seizures, people in the 1800s still thought they were the result of strange forces. They associated seizures with the work of evil spirits. Others felt that the seizures had a cosmic or lunar cause. They believed that the cycles of the moon and stars could make someone have a seizure.

    During a process to treat a patient who has seizures, doctors would force the patient to pray for the grace of the God. They thought if the patient did this, then the patient would rid themselves of the evil spirits causing the seizures.

    The arrival of modern psychiatry(精神病学) occurred during the 1800s. At that time people who suffered from seizures were placed in psychiatric hospitals. They were treated like they were mad. However, none of the out-of-date treatments worked.

    It wasn't until the late 1850s that the causes of seizures were understood. We know today that these causes are related to the brain. Misfired signals from the brain cause a jerking reflex(反射) in the body. These usually occur when someone is very tired.

    Once the causes of seizures were known, definitive treatments were developed. Today, treatments range from taking pills to having surgery. Treatment is personalized according to the type of seizure the patient has.

    Even today, some people are unsure about seizures. Their most common mistake is thinking that a person having a seizure will swallow their tongue. They often push some implement roughly in the person's mouth. However, this doesn't help. The implement often blocks the airway and prevents the person from breathing. Yet most of the public no longer fear people who have seizures. Instead, they can now help and comfort a person if they have a seizure.

My love for libraries blossomed when I joined the public library. From the age of 8 I was allowed to walk from my home to the downtown library, housed above the police station. Once the librarian gave me my first membership card, I could enjoy a range of books, which started with Little House in the Big Woods. I was addicted instantly, and this love of libraries and reading would change my life, allowing me to one day create a safe space for high-school kids, too.

By the time I was in high school, I could read the authors that we were studying in class, including Charles Dickens, Mark Twain and Emily Bronte. During the summer months, I got caught up in Gone with the Wind.

When I studied English literature at university, I thought it was time to build my own library. For the next 40 years, I continued to collect books. Until one day, I realized that all my books had become a part of the house, like wallpaper.

Toward the end of my teaching career, I became a teacher-librarian at my old high school, where I had first learned English literature. This position enabled me to regain my love and appreciation for libraries. I had a generous budget for my classes, so I searched for novels that would interest my teenage audience and hopefully spark a love of books. Fantasy, science-fiction, graphic novels -I bought almost any type of books that my students wanted to read. I bought sofas and comfortable chairs, turning the library into a safe public space, for everyone.

In doing so, I realized that the library isn't just a place to do research. They are, in fact, places that offer an opportunity to connect with the past, present and future. All that is required is a tiny bit of curiosity. Libraries are places that should be full of life. They help us adjust to the world, and their doors must be kept open to everyone for free!