Recently some American scientists have given a useful piece of advice to people in industrialized nations．They say people should eat more of the same kind of food eaten by humans living more than 10,000 years ago．{#blank#}1{#/blank#}

    The scientists say that the human life has changed greatly．Our bodies have not been able to deal with these changes in lifestyle and this had led to new kinds of sicknesses．{#blank#}2{#/blank#} So they are called "diseases of civilization"．Many cancers and diseases of the blood system are examples of such diseases.

    Scientists noted that people in both the Old Stone Age and the New Stone Age enjoyed very little alcohol or tobacco, probably none．{#blank#}3{#/blank#} However, a change in food is one of the main differences between life in ancient times and that of today.

    Stone Age people hunted wild animals for their meat, which had much less fat than domestic ones．They ate a lot of fresh wild vegetables and fruits．They did not have milk or any other dairy products, and they made very little use of grains．{#blank#}4{#/blank#} We eat six times more salt than our ancestors．We eat more sugar．We eat twice as much fat but only one third as much protein and much less vitamin C.

    {#blank#}5{#/blank#} But scientists say that we would be much healthier if we eat much the same way the ancient people did, cutting the amount of fatty, salty and sweet food.

 A．Modern people used to suffer from "diseases of civilization".

 B．People today probably don't want to live like our ancestors.

 C．These new sicknesses were not known in ancient times.

 D．Ancient people also got lots of physical exercise.

 E．In that case, they would live much healthier.

 F．But today, we enjoy eating a lot of these.

 G．Stone Age people lived a simple life.

Urbanization

    Until relatively recently, the vast majority of human being lived and died without ever seeing a city. The first city was probably founded no more than 5,500 years ago. {#blank#}1{#/blank#} In fact, nearly everyone lived on farms or in tiny rural (乡村的) villages.

    It was not until the 20th century that Great Britain became the first urban society in history—a society in which the majority of people live in cities and do not farm for a living.

    Britain was only the beginning.

    {#blank#}2{#/blank#} The process of urbanization—the migration (迁徙) of people from the countryside to the city—was the result of modernization, which has rapidly transformed how people live and where they live.

    In 1900, fewer than 40% of Americans lived in urban areas. Today, over 82% of Americans live in cities. Only about 2% live on farms. {#blank#}3{#/blank#}

    Large cities were impossible until agriculture became industrialized. Even in advanced agricultural societies, it took about ninety-five people on farms to feed five people in cities. {#blank#}4{#/blank#}

    Until modern times, those living in cities were mainly the ruling elite ( 精英) and the servants, laborers and professionals who served them. Cities survived by taxing farmers and were limited in size by the amount of surplus（过剩）food that the rural population produced and by the ability to move this surplus from farm to city.

    Over the past two centuries, the Industrial Revolution has broken this balance between the city and the country. {#blank#}5{#/blank#}

    Today, instead of needing ninety-five farmers to feed five city people, one American farmer is able to feed more than a hundred non-farmers.

A.That kept cities very small.

B.The rest live in small towns.

C.The effects of urban living on people should be considered

D.Soon many other industrial nations became urban societies.

E.But even 200 years ago, only a few people could live in cities.

F.Modernization drew people to the cities and made farmers more productive.

G.Modern cities have destroyed social relations and the health of human beings.

    Do you know that there's a new frontier in 3D printing that's beginning to come into focus: food. Recent development has made possible machines that print, cook, and serve foods on a mass scale. {#blank#}1{#/blank#}

    Food production

    With a 3D printer, a cook can print complicated chocolate sculptures and beautiful pieces for decoration on a wedding cake. {#blank#}2{#/blank#} —it takes years of experience, but a printer makes it easy. A restaurant in Spain uses a Foodini to "re-create forms and pieces" of food that are "exactly the same," freeing cooks to complete other tasks. In another restaurant, all of the dishes and desserts it serves are 3D-printed, rather than farm to table.

    Sustainability

    According to a new study, the global population is expected to grow to 9.6 billion by 2050, and some analysts estimate that food production will need to be raised by 50 percent to maintain current levels. {#blank#}3{#/blank#} 3D food printing could probably contribute to the solution. 3D printing can reduce fuel use and emissions. Grocery stores of the future might stock "food" that lasts years on end, freeing up shelf space and reducing transportation and storage requirements.

Nutrition

    {#blank#}4{#/blank#} Hod Lipson, a professor at Columbia University, said, "Food printing could allow consumers to print food with customized nutritional content, like vitamins. So instead of eating a piece of yesterday's bread from the supermarket, you'd eat something baked just for you on demand."

    {#blank#}5{#/blank#}

    Despite recent advancements in 3D food printing, the industry has many difficulties to overcome. Currently, most ingredients must be changed to a paste(糊状物) before a printer can use them, and the printing process is quite time-consuming, because ingredients interact with each other in very complex ways. On top of that, most of the 3D food printers now are restricted to dry ingredients, because meat and milk products may easily go bad.

A. Challenges

B. Opportunities

C. And the industry isn't stopping there.

D. Sustainability is becoming a necessity.

E. Future 3D food printers could make processed food healthier.

F. Here are some new ways to produce 3D printing.

G. Not everybody can do that.

Much meaning can be conveyed clearly in our eyes, so it is often said that eyes can speak.

{#blank#}1{#/blank#} On a bus you may look at a stranger, but not for too long. And if he senses that you are staring at him, he may feel uncomfortable.

The same is true in our dailylife. If you are stared at for more than necessary, you will look at yourself up and down to see if there is anything wrong with you.{#blank#}2{#/blank#} Eyes do speak, right?

Looking too long at someone may seem to be rude and aggressive. {#blank#}3{#/blank#} If a man stares at a woman for more than 10 seconds and refuses to look away from her, his intentions are obvious. He wishes to attract her attention, and let her know that he is admiring her.

However, when two persons are engaged in a conversation, the speaker will only look into the listener's eyes from time to time to make sure that the listener does pay attention to what the former is speaking. {#blank#}4{#/blank#} If a speaker looks at you continuously when speaking as if he's trying to control you, you will feel awkward. A poor liar usually exposes himself by looking too long at the victim. He wrongly believes that looking straight in the eye is a sign of honest communication. {#blank#}5{#/blank#}

Actually, eye contact should be made based on a specific relationship and situation.

A. On the contrary, it will give him away.

B. Do you have such a kind of experience?

C. That's what normal eye contact is all about.

D. Actually, continuous eye contact is limited to lovers only.

E. After all, everybody likes to be stared at for quite a long time.

F. But things are different when it comes to staring at the opposite sex.

G. If nothing goes wrong, you will feel annoyed at being stared at that way.

    It is not as simple as opening the door and hitting the track in winter. There are a few things you can do to ensure you are getting the most out of your run, and, importantly, not doing more harm than good.

    Warm up, cool down

    {#blank#}1{#/blank#} Your muscles need some time to warm up when it's cold  so take it easy when you set off and do a few stretches (伸展) once you're finished.

    Drink water

    You might not feel hot, but that's because sweat evaporates (蒸发) more quickly into the chilly, dry air. So be sure to drink water before, during and after cold-weather workouts. {#blank#}2{#/blank#} A belt bottle conveniently attaches to your waist so you don't have to carry it and can have a drink whenever you feel like it.

    {#blank#}3{#/blank#}

    Running in cotton is a bad idea. Wear thin, breathable layers of synthetic (合成的) clothing that help protect you from the wind and snow, but still let out heat and moisture (水分).Thirty percent of your body heat escapes through your hands and forty percent through your head. Wear a hat, or beanie (无边小便帽), and gloves so your circulatory system can distribute warm blood to the rest of your body. {#blank#}4{#/blank#}

    Run into the wind

    {#blank#}5{#/blank#} Obviously, it will be an easier passage home with some extra help from Mother Nature. But, more importantly, you won't have the wind in your face for the second half of your run, when you are more likely to be sweating and catch a chill.

Do you ever wish you could change something about your body? If so, you're not alone. {#blank#}1{#/blank#} But when you get stuck on what you don't like, it can really bring down your self-esteem (自尊).

So, want to look and feel your best? Here are some ways:

Accept your body

Nobody's perfect. Everybody wants to be liked and accepted just as they are. Don't body-shame yourself. When you say something negative about your own body, it hurts your self-esteem. {#blank#}2{#/blank#} It hurts just as much as if someone else said it. Be kind and respect yourself.

Like your body

Find things to like about your looks. Maybe you like your hair, face, or hands. What about your shape shoulders, or legs? Your eyes or your smile?{#blank#}3{#/blank#} If you get stuck, think of what your good friends like about how you look.  Accept those things and let yourself feel good.

Take care of your body

Eat healthy foods. Learn what foods are good for you, and how much is the right amount. Eating right helps you look your best. When you treat your body right, you feel good about yourself.

Be active every day. Your body needs to move to be strong, fit and healthy. {#blank#}4{#/blank#} You can run, walk, swim or dance. Pick activities you like and have fun.

Keep to a healthy weight. {#blank#}5{#/blank#} Always talk to your parents or doctor first. But don't try to diet on your own. Your doctor can suggest ways you can stay at a weight that's right for you.

A. Attend to your body's needs.

B. Tell yourself what you like and why.

C. You can be active by playing a sport.

D. You can change a thing about your body.

E. Lots of people feel unhappy with some part of their looks.

F. Being a healthy weight helps you feel good about your body.

G. That's true whether you say it out loud or think it to yourself.