Scotland has long been characterized as a land of romance. It contains ruins of many ancient castles and abbeys，and there is an attractive beauty in its mountains，long deep valleys，and ribbon lakes.Each year those things attract a great number of tourists.

    Numerous islands line the coast.In the north are two large groups，the Orkney Islands and the Shetland Islands.Close to the west coast are the Inner and Outer Hebrides groups，and the islands of Arran and Bute.

    The land may be divided into three regions: the Highlands in the north，the Central Lowlands and the Southern Uplands.

    The Highlands are wild and picturesque(如画的)． A long valley called Glenmore crosses the Highlands from southwest to northeast.

    In the south of the Highlands are the Grampian Mountains，highest in the British Isles. Ben Nevis，the highest peak，rises to 1,243 meters.Ben Lomond rises from the shore of Loch Lomond，Scotland's largest freshwater lake.

    The Central Lowlands run from southwest to northeast and the greatest length is nearly 145 kilometers.The soil here is fertile，and there are four coalfields underlying the area.In the east is Edinburgh，Scotland's historic capital city，and in the west is Glasgow. Almost 90 percent of Scotland's population live in the Lowlands.

    In the Southern Uplands, the hills are generally less than 600 meters high. Their rounded or flat tops are often capped with dark peat(泥炭). Along the slopes are plants like grass and heather(石南花).

    Below is a selection from a popular science book.

    If blood is red, why are veins（静脉） blue?

    Actually, veins are not blue at all. They are more of a clear, yellowish color. Although blood looks red when it's outside the body, when it's sitting in the vein near the surface of the skin, it's more of a dark reddish purple color. At the right depth, these blood-filled veins reflect less red light than the surrounding skin, making them look blue by comparison.

    Which works harder, you heart or your brain?

    That kind of depends on whether you're busy thinking or busy exercising. Your heart works up to three times harder during exercise, and shifts enough blood over a lifetime to fill a supertanker. But in the long run, your brain probably tips it, because even when you're sitting still your brain is using twice as much energy as your heart, and it takes four to five times as much blood to feed it.

    Why do teeth fall out, and why don't they grow back in grown-ups?

    Baby (or “milk”) teeth do not last long; they fall out to make bigger room for bigger, stronger adult teeth later on. Adult teeth fall our when they become damaged, decayed and infected by bacteria. Once this second set of teeth has grown in, you're done. When they're gone, they are gone. This is because nature figures you're set for life, and what controls regrowth of your teeth switches off.

    Do old people shrink as they age?

Yes and no. Many people do get shorter as they age. But, when they do, it isn't because they're shrinking all over. They lose height as their spine（脊柱） becomes shorter and more curved due to disuse and the effect of gravity(重力). Many (but not all) men and women do lose height as they get older. Men lose and average of 3-4 cm in height as they age, while women may lose 5 cm or more. If you live to be 200 years old, would you keep shrinking till you were, like 60 cm tall, like a little boy again? No, because old people don't really shrink! It is not that they are growing backwards —- their legs, arms and backbones getting shorter. When they do get shorter, it's because the spine has shortened a little. Or, more often, become more bent and curved.

    Why does spinning make you dizzy（眩晕的）?

    Because your brain gets confused between what you're seeing and what you're feeling. The brain senses that you're spinning using special gravity-and-motion-sensing organs in your inner ear, which work together with your eyes to keep your vision balance stable. But when you suddenly stop spinning the system goes out of control, and your brain thinks you'removing while you're not.

    Where do feelings and emotions come from?

Mostly from an ancient part of the brain called the limbic system. All mammals have this brain area —- from mice to dogs, cats, and humans. So all mammals feel basic emotions like fear, pain and pleasure. But since human feelings also involve other, newer bits of the brain, we feel more complex emotions than any other animal on this planet.

    If exercise wears you out, how can it be good for you?

    Because our bodies adapt to everything we do to them. And as far as your body is concerned, it's “use it, or lose it”! It's not that exercise makes you healthy, it's more that a lack of exercise leaves your body weak and easily affected by disease

    Food is one of the necessities in our daily life. It serves as a form of communication in two fundamental ways. Sharing bread or other foods is a common human tradition that can promote unity and trust. Food can also have a specific meaning, and play a significant role in a family or culture's celebrations or traditions. The foods we eat—and when and how we eat them—are often unique to a particular culture or may even differ between countrysides and cities within one country.

    Sharing bread, whether during a special occasion or at the family dinner table, is a common symbol of togetherness. Many cultures also celebrate birthdays and marriages with cakes that are cut and shared among the guests. Early forms of cake were simply a kind of bread, so this tradition hits its roots in the custom of sharing bread.

    Food also plays an important role in many New Year celebrations. In the southern United States, pieces of corn bread represent blocks of gold for prosperity (兴旺) in the New Year. In Greece, people share a special cake called vasilopita. A coin is put into the cake, which signifies (预示) success in the New Year for the person who receives it.

    Many cultures have ceremonies to celebrate the birth of a child, and food can play a significant role. In China, when a baby is one month old, families name and welcome their child in a celebration that includes giving red-colored eggs to guests. In many cultures, round foods such as grapes, bread, and moon cakes are eaten at welcome celebrations to represent family unity.

    Nutrition is necessary for life, so it is not surprising that food is such an important part of different cultures around the world.

    A walker seriously injured in a mountain­top lightning strike which killed two others is showing signs of improvement, the police have said. A major rescue operation was performed on Sunday following two strikes which hit the Brecon Beacons, South Wales. Two men died, while two others were taken to hospital.

    A police spokeswoman said, "A man in a serious condition in hospital, following simultaneous(同时发生的)incidents in the Brecon Beacons, has now improved and he is recovering. Officers are continuing to get in touch with the next of relatives of the dead men and enquiries are ongoing. All men were believed to be from England."

    Mark Jones,of the Brecon Mountain Rescue Team, described the lightning strike as a freak accident, and something he had not been called out to in 30 years of service.

    The walking group Ramblers Cymru said that while incidents involving thunder and lightning were rare  electrical storms should be taken seriously by walkers.

    The organisation's delivery officer, Elly Hannigan Popp, said, "We'd advise everyone to check the weather forecast before starting a walk. If you hear thunder, see lightning or if your hair stands on end, postpone activities even if the sky looks blue and clear. Lightning will strike as far as 10 miles away from any rainfall. Lightning can strike the same place repeatedly—especially tall, pointed, isolated objects."

    "If there is no shelter you should keep moving. And if you become the tallest object, crouch(蹲)in the open twice as far away from the nearest pointed object as it is tall. Make yourself as small as possible, stay on your toes and keep your heels together, as it will allow electricity to go up one foot, through the heels and back into the ground through the other."

The famous Spanish painter Pablo Picasso once said, "I am always doing that which I cannot do, in order that I may learn how to do it." It strikes a chord(引起共鸣) with me because that's exactly what I have been doing these years.

One of my earliest memories of doing before learning is baking scones(烤饼) when I was about 10 years old. I wanted to bake them to surprise my mother when she returned home.

Before that, I'd observed how my mother baked them many times. As I started to try, I didn't know I shouldn't handle the dough(面团) with my hands too much once I'd added the baking powder(发酵粉). However, I knew exactly how to roll out the dough and use a cookie cutter to cut the scones, because my mom had already taught me.

By the time my mom arrived home, the smell of freshly baked scones welcomed her into the kitchen. They were close to perfection—flat, as a result of overhandling the dough, but they tasted OK. My mom sweetly praised me for my attempt, rather than scolding me for the state of the kitchen, which was like a tornado had just blown!

Have my attempts always been successful? I wish! Some of my kitchen disasters were so terrible that even the dogs wanted nothing to do with them. My gardening failures didn't live to see another season.

But my habit of doing before learning is still helpful. Whatever new software I have to learn how to use, I do so by simply starting to use it. I do, learn, and improve. So if you ask me whether I regret that I tend to do first and learn later, I'd say I don't, because what I have discovered from those is the wisdom to know when it's OK to do and then learn, and when it's probably better to learn and then do!

Advances in generative artificial intelligence (AI) have enabled authentic-sounding speech synthesis (语音合成) to the point that a person can no longer distinguish whether they are talking to another human or a deepfake (深度伪造). If a person's own voice is "cloned" by a third party without their agreement, bad guys can use it to send any message they want.

Computer scientist and engineer Ning Zhang has developed a new method to prevent unauthorized speech synthesis before it takes place: a tool called AntiFake.

Traditional deepfake detection methods only work after the damage is done. However, AntiFake prevents voice data from being synthesized into an audio deepfake beforehand. This tool turns the tables on cybercriminals (网络罪犯) by using similar voice cloning techniques they employ, but for voice protection. The software complicates voice data extraction and feature identification crucial for voice synthesis. "We're using an opposite AI technique originally used by cybercriminals, but now we're using it against them," Zhang explained. "We slightly change the recorded audio, just enough to make it unusable for voice clone training while still sounding natural to humans."

Ben Zhao, a professor of computer science at University of Chicago, says that the software, like all digital security systems, will never provide complete protection. But, he adds that it can raise the bar and limit the attack to a smaller group of individuals with significant resources.

AntiFake can already protect shorter voice recordings against cloning. The creators of the tool believe that it could be extended to protect larger audio documents or music from misuse. But the methods and tools that are developed must be continuously adapted because cybercriminals will learn and grow with them.