Soda is refreshing and delicious, but it is not part of a healthy, balanced diet. Most sodas are packed with sugar. In fact, a can of soda can be hiding up to 10 teaspoons of sugar! The sugar does make soft drinks delicious, but definitely not nutritious. Too much sugar in a person's diet can lead to diabetes (糖尿病), heart disease, and tooth problems. One of the biggest sugary soda problems is that drinking much can lead to weight gain and even obesity.

    There are diet options available for almost every kind of pop (汽水), which means that you don't have to drink all that sugar in order to enjoy a can of soda. Many studies have been done on whether or not aspartame (甜味剂), the sugar substitute in diet soda, is bad for you. Up to now, there are still conflicting opinions on this issue. The European Food Safety Authority recently concluded that aspartame is safe for most people, even in fairly large amounts. Aspartame still might not be good for you, though. Studies have shown that people who drink diet sodas may actually gain more weight than those who drink regular soda, perhaps because, strangely enough, drinks loaded with fake sugar may actually make you want to eat more.

    Maybe you've decided it's time to cut down on your soda drinking, but what should you drink instead? Water is absolutely the healthiest thing that you can drink. Your body needs water to stay hydrated (水合物) and function properly, and water contains no calories or fat. Drinking fruit juice occasionally is not a bad thing, but you should be careful what juice and how much juice you're drinking. Fruit juices can contain almost as much sugar as pop!

    As with most things to do with your health, moderation is really at the base of any healthy diet. You can totally drink soda, even the sugary kind just, make sure you're not drinking too much!

    Are you sometimes a little tired and sleepy in the early afternoon? Many people feel this way after lunch. They may think that eating lunch is the cause of the sleepiness. Or, in summer, they may think it is the heat. However, the real reason lies inside their bodies. At that time—about eight hours after you wake up—your body temperature goes down. This is what makes you slowdown and feel sleepy. Scientists have tested sleep habits in experiments where there was no night or day. The people in these experiments almost always followed a similar sleeping pattern. They slept for one long period and then for one short period about eight hours later.

    In many parts of the world, people take naps in the middle of the day. This is especially true in warmer climates, where the heat makes work difficult in the early afternoon. Researchers are now saying that naps are good for everyone in any climate. A daily nap gives one a more rested body and mind and therefore is good for health in general. In countries where naps are traditional, people often suffer less from problems such as heart disease. Many working people, unfortunately, have no time to take naps. Though doctors may advise taking naps, employers do not allow it! If you do have the chance, however, here are a few tips about making the most of your nap. Remember that the best time to take a nap is about eight hours after you get up. A short sleep too late in the day may only make you feel more tired and sleepy afterward. This can also happen if you sleep for too long. If you do not have enough time, try a short nap—even ten minutes of sleep can be helpful.

    To help the environment, many Americans have made the change from paper and plastic(塑料的) bags to reusable shopping bags. But a report by a Florida newspaper says that reusable shopping bags sold by some supermarkets have high levels of lead (铅), which can be dangerous to humans, especially young children. Now, there's a call for a rethink about the use of reusable shopping bags.

    “When our families go to the store looking for safe and healthy foods, the last thing they should be worrying about is a bag,” Charles Schumer, a government official said.“ Quick and complete research will allow everyone to make right decisions.”

    The newspaper bought more than a dozen bags sold at Publix supermarkets from Florida supermarkets to test them for lead. The results showed that certain bags had lead levels that worried health officials. Some bags had enough lead in them to be considered dangerous waste if people were to throw the bags out with other rubbish. Lead in the bags may not move onto food. But over time, paint on the bags can break off and the bags can wear out. When this happens, lead can be freed.

    The bags with the highest levels of lead had beautiful designs and many pictures. Plain （朴实无华的） reusable bags without them are found to have little lead. People worried about lead levels in reusable bags can turn to cloth. Paper bags are also a good choice, since paper can be reused.

    "Hope has proved a powerful predictor of outcome in every study we've done so far," said Dr. Snyder, a psychologist.

    In research with 3,920 college students, Dr. Snyder found that the level of hope among freshmen at the beginning of their first term was a more accurate predictor of their college grades than were their S.A.T. scores or their grade point averages in high school. "Students with high hope set themselves higher goals and know how to work to attain them," Dr. Snyder said. "When you compare students with equal learning ability and past school achievements, what sets them apart is hope."

    In seeking a way to assess hope scientifically, Dr. Snyder went beyond the usual belief that hope is merely the sense that everything will turn out all right. "This idea is not concrete enough; it fails to clarify two key components of hope," Dr. Snyder said.

    "Having hope means believing you have both the will and the way to accomplish your goals, whatever they may be."

    Despite the wisdom in the old saying "where there's a will there's a way," Dr. Snyder has found that the two are not necessarily connected. In a study of people from 18 to 70 years old, Dr. Snyder discovered: only about 40% of people are hopeful in the technical sense of believing they typically have the energy and means to accomplish their goals; about 20% of the people believed in their ability to find the means to attain their goals, but said they had little will to do so; another 20% have the opposite pattern, saying they had the energy to motivate themselves but little confidence that they would find the means; the rest had little hope at all, reporting that they typically had neither the will nor the way.

    "It's not enough just to have the wish for something," said Dr. Snyder. "You need the means, too. On the other hand, all the skills to solve a problem won't help without the willpower to do it."

    In the kitchen of my mother's houses there has always been a wooden stand (木架)with a small notepad(记事本)and a hole for a pencil.

    I'm looking for paper on which to note down the name of a book I am recommending to my mother. Over forty years since my earliest memories of the kitchen pad and pencil, five houses later, the current paper and pencil look the same as they always did. Surely it can't be the same pencil. The pad is more modern, but the wooden stand is definitely the original one.

    "I'm just amazed you still have the same stand for holding the pad and pencil after all these year." I say to her, walking back into the living-room with a sheet of paper and the pencil. "You still use a pencil. Can't you afford a pen?"

    My mother replies a little sharply. "It works perfectly well. I've always kept the stand in the kitchen. I never knew when I might want to note down an idea, and I was always in the kitchen in those days."

    Immediately I can picture her, hair wild, blue housecoat covered in flour, a wooden spoon in one hand, the pencil in the other, her mouth moving silently. My mother smiles and says, "One day I was cooking and watching baby Pauline, and I had a brilliant thought, but the stand was empty. One of the children must have taken the paper. So I just picked up the breadboard and wrote it all down on the back. It turned out to be a real breakthrough for solving the mathematical problem I was working on."

    This story—which happened before I was born—reminds me how extraordinary my mother was, and is, as a gifted mathematician. I feel embarrassed that I complain about not having enough child-free time to work. Later, when my mother is in the bathroom, I go into her kitchen and turn over the breadboards. Sure enough, on the back of the smallest one, are some penciled marks I recognize as mathematics. Those symbols have traveled unaffected through fifty years, rooted in the soil of a cheap wooden breadboard, invisible(看不到的)exhibits at every meal.

    Most animals on land are known to us, but many living things underwater are not. Now let's get to know some of them.

    Sea cucumber

    Sea cucumber are strange animals living at the bottom of the sea. They wear brown or pale green coats with many sticks up. When summer comes, they stay deep to sleep because they are afraid of heat. And when it is autumn, they move to shallow (浅的) water and get their food.

    Pike

    The pike is a kind of freshwater fish. They are good swimmers and like swimming near boats, waiting to be fed. They have sharp teeth to catch fishes. When they are young, they live in groups. However, when they grow up, they prefer to live alone.

    Cuttlefish

    A cuttlefish can swim quite fast, so it is also called rocket (火箭) fish. It has eight arms and two feelers on its head, just around its mouth. It ejects ink (喷墨) when it is in danger. Its meat is delicious, and it is often the first choice for many people.

    Octopus

    An octopus has long arms, with which to catch food and protect itself. When it is sleeping, one or two of its arms are still on duty, keeping moving. Once it feels something dangerous, it can wake up at once to take action.