Smoking is harmful. But as soon as you give up the habit, everything will be OK, right? Wrong.
New research has found that even if you give up smoking, the damage it has done to your genes (基因) will stay there for a much longer time.
In the research, a team of US scientists studied the blood of 16,000 people. Among them, some were smokers, some used to smoke, and the rest were non-smokers. Scientists compared their genes and found that more than 7,000 genes of smokers had changed.
The process (过程) that smoking makes changes to your genes is called “methlation”. It affects how your genes act—whether they are turned on or turned off.
According to NBC News, both heart disease and cancer are caused by genetic changes. Some people may have had the changes when they were born, but most people get them in their day-to-day lives while doing things like smoking.
When you stop smoking, a lot of these genes will return to normal in five years. This means your body is trying to cure itself of the harmful effects of smoking. But the changes in some of the genes stay for longer. They can stay for as long as 30 years. It’s almost like leaving a footprint on wet cement (水泥)—it will always be there, even when you’ve walked away and when the cement becomes dry.
Although the study results may make people unhappy, there is a bright side: the findings could help scientists invent medicine to treat genetic damage caused by smoking or find ways to tell which people have heart disease or cancer risks.
People who have just stopped smoking or are planning to do so shouldn’t feel bad about their choice either, because “the sooner you can stop smoking, the better you will be”, suggested Stephanie at National Institute of Environment Health Science.
1. The function of Paragraph 1 is to ________.| A．give an example | B．make an argument |
| C．show the main idea of the passage | D．introduce the topic of the passage |
| A．environmental pollution | B．heart disease and cancer |
| C．people’s bad living habits | D．people’s condition at birth |
| A．the cement | B．the footprint | C．the harmful effect | D．the genetic change |
| A．The findings are the fruit of more than three years’ research. |
| B．The findings offer evidence that a damaged gene can heal itself. |
| C．The findings have prevented more people from starting working. |
| D．The findings help to find cures for genetic damage caused by smoking. |
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【推荐1】Chemical reactions (化学反应) make for some great experiments. You can make use of the CO2 (carton dioxide) given off by a baking soda and lemon juice reaction to blow up your balloon!
What you’ll need:
★Balloon.
★About 40ml of water (a cup is about 250ml, so you don’t need much).
★Soft drink bottle.
★Juice from a lemon.
★1 teaspoon of baking soda.
Instructions:
★Before you begin, make sure that you pull the balloon long to make it as easy as possible to blow up.
★Put the 40 ml of water into the soft drink bottle.
★Add the baking soda and mix it with water.
★Put the lemon juice in and quickly put the balloon over the mouth of the bottle.
What’s happening?
If all goes well, then your balloon should inflate (使充气)! Adding the lemon juice to the baking soda creates a chemical reaction and produces CO2. The gas rises up and escapes through the soft drink bottle. It doesn’t, however, escape the balloon, pushing it outwards and blowing it up.
根据材料内容选择最佳答案。
1. Which of the following do you need for the experiment?
| A．Two cups. | B．Apple juice. |
| C．250ml water. | D．A teaspoon of baking soda. |
| A．Heat the water. | B．Drink some juice. |
| C．Blow up the balloon. | D．Pull the balloon long. |
| A．Baking soda. | B．Water. | C．Juice. | D．A balloon. |
| A．To describe an experiment. | B．To introduce a game. |
| C．To produce soft drinks. | D．To save some chemicals. |
| A．An advertisement. | B．A movie poster. |
| C．A science magazine. | D．A news report. |
【推荐2】Robots may seem smart, but they cannot even pick up a chess piece. Let’s take a look at some tasks that are easy for kids but not for robots.
Pick things up
Picking things up is not easy. If we drop our pencil on the floor, our brains work hard. First, we must find the pencil. Then we move our hands to it. A robot cannot always move its “hand” to the right place. When we touch the pencil, it might roll (滚动) a little bit. Robots cannot easily understand this either. So, if you drop a pencil on the floor, a robot will probably roll it around the room.
Get around in large space
If someone drops us in a building we’ve never been to, we might feel a bit lost. But we can look around, find a door and get out quickly. But a robot will look everywhere for a door, even on ceilings and floors. This is because it’s hard for them to understand spaces, especially large, blank things such as walls or ceilings.
Understand the world made by people
“Common sense” is what we don’t need to think or talk about. Because of common sense, we do not look for doors on the ceiling. We pick up a coffee cup by its handle (把手). We feel whether it has coffee inside, and whether it’s hot.
A robot? It may turn the cup upside down. It may hold the hot part of the cup. Scientists have tried teaching robots common-sense rules. But even huge databases (数据库) don’t help much. Maybe they need more time to learn.
1. What will a robot do in order to find a door?| A．Dig a big hole in the wall. |
| B．Only look for large and blank things. |
| C．Search everywhere even the ceilings. |
| D．Drop itself in a corner in the building. |
| A．Robots can teach themselves common sense. |
| B．Robots have the same common sense as humans. |
| C．Scientists tried teaching robots common-sense rules. |
| D．Huge databases help much for robots to learn common sense. |
| A．Robots are not helpful to humans at all. |
| B．Robots are good at picking up small things. |
| C．It is easy for robots to understand large spaces. |
| D．Robots have trouble understanding our world. |
【推荐3】You might think that drinking fruit juice is healthy. But that’s not quite true. A study (研究) shows that drinking too much juice — even 100% fruit juice — will do great harm to your health and can even make you die early.
This is because these drinks have a lot of sugar. Scientists said drinking too much fruit juice is just like drinking too much soda (汽水) — they both have a lot of sugar. Eating too much sweet food can cause many health problems, such as getting fat and heart disease. Fruit juice has vitamins (维生素) , but there are very few vitamins in it.
In the study, both soda and 100% fruit juice are “ sweet drinks” . Scientists found that if people get 10% or more of their energy from sweet drinks every day, they may die from heart disease or other diseases. Jean Welsh, one of the scientists in the study, told CNN, “ People should drink less sweet drinks, whether soda or fruit juice. ”
Does this mean that eating fruit is also unhealthy? Fruit is still fine. When you eat 100g of fruit, you’re getting less sugar than if you drink 100g of juice, because the fruit has lots of fiber (纤维) . This fiber is also good for our health. It’s better to eat the whole fruit instead of fruit juice.
根据材料内容选择最佳答案。
1. What will happen if people eat too much sugar every day?
| A．They will become thinner. |
| B．They will get fewer vitamins. |
| C．They might have sleep problems. |
| D．They might die from heart disease. |
| A．Fruit juice. | B．Sweet drinks. | C．Soda. | D．Sugar. |
| A．Fruit has lots of fiber. |
| B．Fruit juice has lots of sugar. |
| C．It’s better to drink more fruit juice. |
| D．People shouldn’t drink more sweet drinks. |
| A．Fruit juice is a kind of sweet drink. |
| B．People have too much sugar every day. |
| C．Drinking soda can cause many health problems. |
| D．Eating the whole fruit is better than drinking fruit juice. |
| A．Culture. | B．Health. | C．Science. | D．Life. |
If you want to do a school project on children’s rights (权利), you can look on the Internet for some information.
The United Nations lists the rights of children. Most countries agree all of them, but some countries do not.
◆Children have the right to be properly fed, clothed and sheltered (庇护) by their family. If their family can’t do so, the government should take responsibility.
◆Children have the right to an education and medical care.
◆Children must not be cruelly punished by their parents or any others.
◆Children have the right to expect the government to protect them from all kinds of abuse (虐待) and neglect (忽略).
◆
◆Children have the right to be protected from being made to work too hard to make money for other people.
In some countries children do not have these rights. Many young children are made to work long hours in factories and on farms. In some countries there are so few schools that only rich children get an education.
The rights of children are, therefore, the rights people think children should have. They are not always the rights children really have.
| A．Children mustn’t fight at school. |
| B．They should be provided by the government. |
| C．No child under fifteen should be made to fight in an army. |
| D．The following are some of the most important rights of children. |
| E．There are not enough doctors or nurses to help many children when they are sick. |
| F．A United Nations website can show you plenty of useful information for the project. |
【推荐2】Asking for help can feel scary. We may worry that the requests(请求) will be refused. But a new research shows that people are gladder to help out than we think.
Scientists performed some experiments(实验). In one experiment, participants(参与者) had to ask strangers to take a photo for them in the park. In another, participants answered questions when they had asked for or been given help. Researchers let people guess how the “helpers” might feel about the requests. Then they asked the helpers how they really felt.
In each experiment, people who asked for help underestimated the helpers’ gladness to help and how good they would feel. For example, people thought strangers would feel uncomfortable when being asked to take a photo. However, only 4 out of 100 people refused to take the photo, and those who did take one said they felt relaxed about doing this helpful act for a stranger.
The study also showed that askers’ fears stopped them from asking for help. Experts said that if asking for help made people feel uncomfortable, it could be useful to practice. A study which came out earlier this year found that people thank acts of kindness much more than expected. The researchers found that the recipients(接受者) praise the acts much more than the givers thought.
1. What does the new research show?| A．It is easy to offer help to others. | B．People are glad to offer help to others. |
| C．People are afraid to ask strangers for help. | D．People can’t ask for what they really want. |
| A．打击 | B．转述 | C．低估 | D．凝聚 |
| A．Calling on people to take photos. |
| B．Showing the result of this research. |
| C．Teaching students how to do such a research. |
| D．Encouraging people to ask for help and help others. |
On a hot summer day, you find the pond has almost dried up. Where did the water go? It goes into the air! Each drop of water is made of droplets. When the sun warms them, they go up and become part of the air. However, do you know how rain is formed (形成)?
High in the sky, the air is cooler. As the water in the air cools, it changes back into droplets. They get together to make clouds.
In the clouds, many many droplets get together and grow bigger. When they are heavy enough, they fall from the sky as raindrops, or if it’s very cold-snowflakes! The water we have on the earth is always moving and changing!
We’ve seen how the sun heats the water so it goes up, cools, and becomes a cloud. In the cloud, droplets join together to become raindrops, and fall back to the earth. Some rainwater goes u again soon, while some joins rivers, lakes, or the ocean. This is called the water cycle.
Rain falls almost everywhere on the earth. One of the world’s rainiest places is Mount Waialeale in Hawaii. It rains about 350 days a year there. One of the driest places on the earth is the Atacama Desert in Chile. It has not rained in some parts of this desert in hundreds of years.
1. Where does the water in the pond go in hot summer?| A．It goes into the rivers. | B．It goes into the lakes. | C．It goes into the air. |
| A．They’ll fall from the sky as raindrops. |
| B．They’ll get together and stay in the air. |
| C．They’ll go up and become part of the air. |
| A．How are rivers and lakes formed? |
| B．How often does it rain in Mount Waialeale? |
| C．Why does the air high in the sky become cooler? |
A． | B． | C． |
| A．Education. | B．Science. | C．Travel. |
