1 . Germs(细菌) are everywhere. You can’t see them, but they are on your desk, on your computer, and even in the air!
Like people, germs move around the world. They fly with us on planes. When food, clothes, and other things travel around the world, germs travel, too. Some germs are safe, but some are dangerous. Germs cause illnesses like colds and the flu.
Warmer Weather Brings Germs
The world’s weather is changing. Cooler countries are getting warmer, so insects from hot countries can move there. Some of these insects, like mosquitoes, carry dangerous germs. These germs cause headaches, fever, and can even kill people.
Under Your Skin
Your skin protects you from germs. It stops some germs, but not all. They can enter your body when you eat, or when you have a cut. Germs are on your hands, too. They enter your body when you touch your eyes, nose, or mouth.
Fighting Germs
Your immune system(免疫系统) protects you, too. When germs get inside your body, your immune system finds and kills them. Special cells(细胞) move around your body and fight germs. They help you stay healthy. Other cells make antibodies. Antibodies help your body find and stop germs.
What can you do to fight germs? You should wash your hands with soap and water. Soap kills many germs, and water washes them away.
1. According to the text, insects ______.| A．kill germs | B．carry germs | C．protect germs | D．love germs |
| A．cooler countries | B．hot countries | C．everywhere | D．the world |
| A．All germs are dangerous. | B．There are more germs in cold places. |
| C．Soap can kill all germs. | D．Germs can get into your body. |
| A．They kill germs and wash them away. | B．They find and develop germs. |
| C．They help protect us from germs. | D．They carry dangerous germs. |
| A．Germs Are Everywhere | B．Weather Is Changing |
| C．Skin Stops Germs | D．Germs Are Developed |
2 . A tracked robot approaches a pile of brushwood blocking its path. This is Rolan, short for Robot Manipulator (操控者), who is practising for what is its graduation ceremony, when it will show off its skills. After a pause, it reaches out an arm, takes hold of a branch, lifts it up and drags it clear.
Though this is a small action for a human being, it is a breakthrough for robots, according to Stuart Young of the Army Research Laboratory, who is in charge of the RoMan project. As is known, robots easily become confused by something unexpected, some unfamiliar and none with convenient handles. Taking it apart is far beyond the power of any industrial robot. Dr. Young says that, as far as he knows, RoMan is the first machine able to manipulate unfamiliar objects in an unknown environment.
Just as a human being would, it has to learn about the world through observation and experiment before manipulating it. So it is trained on numerous tree branches until it is able to recognize unfamiliar ones for what they are and knows to grasp the trunk, rather than the leaves or the branches. Having grasped an object, RoMan assesses its weight and decides whether to try to lift it or drag it.
Dr. Young hopes to take this further by dealing with piles of burning tyres. He also wants RoMan to be able to use its body weight in the way a human being might to push open a tight door or to move heavy furniture by bracing against a wall. One problem with RoMan is that it is still impractically slow. It often takes 10-15 seconds to decide what to do. RoMan will also need to learn to deal with a wider range of objects.
However, the device's future could be bright. Beyond military applications, its following generations might work in warehouses, pick fruit, clear litter or tidy people's homes. They might even collect rocks from the surface of Mars.
1. Why does RoMan take a pause before taking action?| A．The branch is too heavy for it. |
| B．It is reflecting on its next move. |
| C．It takes time to show off its skills. |
| D．It is totally confused by the mess. |
| A．Everything existing around. |
| B．Observation before manipulating. |
| C．The similarity to a human being. |
| D．RoMan's ability acquired by training. |
| A．The author's wish for RoMan. | B．The power of RoMan's weight. |
| C．Dr.Young's regret for RoMan. | D．RoMan's room for improvement. |
| A．Sports&Entertainment. | B．Health&Medicine. |
| C．Education&Career. | D．Science&Technology. |
3 . With chip (芯片)readers, auto-reload apps, and one-dick online purchasing, it’s only too easy to buy something without fully registering how much it costs. That said, even if you’re not counting out small change for the cashier these days, you’ve probably still noticed how often prices end in .99.
Maybe you assumed it had something to do with tax laws, or else it was a leftover practice from decades ago, when things cost less and pennies mattered more. In fact, it’s actually a clever psychological tool that tricks your brain into thinking the price of an item is lower. “Because we read from left to right, we pay less attention to the end of the number versus (与……相比) the beginning,” DealNews.com consumer analyst Julie Ramhold told Reader’s Digest. So, for example, your mind will interpret $9.99 as $9. though it’s obviously much closer to $10.
Just one dollar’s difference might not seem like enough to a fleet your decision on whether to buy something, but it can push an item into a lower price range—and that’s enough to make your mind think it costs significantly less. To your subconscious brain, a one-digit (一位数的)price like $9 seems a lot cheaper than a two-digit price like $10.
Though ending prices in 9 might be the norm, there is a fair amount of variation when it comes to retailers’ pricing tactics (定价策略). Live Science reports that because we often see a price ending in 9 as a cheap deal, some stores—like J. Crew and Ralph Lauren—save the nines for their sale items, and use numbers ending in 0 for their full-priced items, giving the impression that those items are high-quality. Thrift stores (二手商店),on the other hand, often use whole numbers for all their products.
1. What does the underlined word “it” refer to?| A．an auto-reload app | B．a chip |
| C．one-click | D．something |
| A．Ending in .99 is a mentally low price. |
| B．Ending in .99 is a reasonable price. |
| C．Ending in .99 is a fit to tax laws. |
| D．Ending in .99 is a one-digit lower price. |
| A．To show the items are cheap enough. |
| B．To show the items are in high-quality. |
| C．To show the items are fit for the norm. |
| D．To show the items are different enough. |
| A．Buy What You Want at the Right Prices |
| B．Why Are So Many Prices Lower? |
| C．The Reason So Many Prices End in .99 |
| D．Saving the Nines for Your Purchasing Items |
4 . A few weeks ago, I bought a locally-grown salad from a vending machine(自动售货机). But then I immediately realized that it was packaged in a plastic jar. ''I guess I live with this jar now and forever. '' I thought sadly as I stared down at my new child.
The salad jar was only the latest in a long line of examples of how I am addicted to the responsibility of reusing everything, trying to never throw anything away. Water bottles have been given second lives, and berry containers are transformed into Tupperware. I recently even looked at a plastic straw in my fruit juice: Could I reuse it too…?
Yet trying to squeeze my salad jar under my kitchen counter this weekend, I finally had to admit: Being an environmentalist has turned me into a hoarder(囤积者). While keeping a certain number of jars and vegetable bags will allow me not to buy new containers, at a certain point those 30 berry containers begin to get a bit unnecessary. Who am I kidding? Then one day I came across a blog post that asks accusingly. ''Are you turning your own home into a landfill(垃圾填埋场)? ''
In my defense, there is absolutely no excuse not to be a conscious consumer. The solution is painfully obvious, but hard to admit: Delaying waste is not, in fact, rejecting waste. In an over-packaged, over-consuming culture, this can feel like a burden. While I refuse to throw away packaging, the fact remains: I already have it. The damage is done. I've been ignoring one of the most essential and difficult parts—reduce, reuse, recycle. Even if I go out of my way to reuse the waste I do have, I need to reduce what I am bringing home in the first place.
While I might not be ready to go full zero-waste, it's a goal that is admirable to work toward. Until then, my salad jar child is going to make a great overnight oats jar.
1. What does the author try to indicate by the last sentence in paragraph 2 ?| A．How important reusing is. |
| B．How enthusiastic she is about reusing. |
| C．How she makes use of the plastic straw. |
| D．Why she is responsible for reusing plastic straws. |
| A．She enjoys collecting a variety of small jars. |
| B．She has saved far more containers than she needs. |
| C．She likes the idea of saving fine packages in daily life. |
| D．She stores more berry containers than other containers. |
| A．Over-packaging. | B．Delaying waste. |
| C．Over-consuming. | D．Rejecting waste. |
| A．buy fewer over-packaged goods |
| B．throw away unnecessary packaging |
| C．reuse materials as much as possible |
| D．appreciate the value of recycling materials |
5 . No one is sure how the ancient Egyptians built the pyramids near Cairo. But a new study suggests they used a little rock ‘n’ roll. Long-ago builders could have attached wooden poles to the stones and rolled them across the sand, the scientists say.
“Technically, I think what they’re proposing is possible,” physicist Daniel Bonn said.
People have long puzzled over how the Egyptians moved such huge rocks. And there’s no obvious answer. On average, each of the two million big stones weighed about as much as a large pickup truck. The Egyptians somehow moved the stone blocks to the pyramid site from about one kilometer away.
The most popular view is that Egyptian workers slid the blocks along smooth paths. Many scientists suspect workers first would have put the blocks on sleds(滑板). Then they would have dragged them along paths. To make the work easier, workers may have lubricated the paths either with wet clay or with the fat from cattle. Bonn has now tested this idea by building small sleds and dragging heavy objects over sand.
Evidence from the sand supports this idea. Researchers found small amounts of fat, as well as a large amount of stone and the remains of paths.
However, physicist Joseph West thinks there might have been a simpler way, who led the new study. West said, “I was inspired while watching a television program showing how sleds might have helped with pyramid construction. I thought, ‘Why don’t they just try rolling the things?’ ”A square could be turned into a rough sort of wheel by attaching wooden poles to its sides, he realized. That, he notes, should make a block of stone “a lot easier to roll than a square”.
So he tried it.
He and his students tied some poles to each of four sides of a 30-kilogram stone block. That action turned the block into somewhat a wheel. Then they placed the block on the ground.
They wrapped one end of a rope around the block and pulled. The researchers found they could easily roll the block along different kinds of paths. They calculated that rolling the block required about as much force as moving it along a slippery(滑的) path.
West hasn’t tested his idea on larger blocks, but he thinks rolling has clear advantages over sliding. At least, workers wouldn’t have needed to carry cattle fat or water to smooth the paths.
1. It’s widely believed that the stone blocks were moved to the pyramid site by .| A．rolling them on roads | B．pushing them over the sand |
| C．sliding them on smooth paths | D．dragging them on some poles |
| A．Rolling the blocks with poles attached. |
| B．Rolling the blocks on wooden wheels. |
| C．Rolling poles to move the blocks. |
| D．Rolling the blocks with fat. |
| A．Because more force is needed for sliding. |
| B．Because rolling work can be done by fewer cattle. |
| C．Because sliding on smooth roads is more dangerous. |
| D．Because less preparation on paths is needed for rolling. |
| A．An experiment on ways of moving blocks to the pyramid site. |
| B．An application of the method of moving blocks to the pyramid site. |
| C．An argument about different methods of moving blocks to the pyramid site. |
| D．An introduction to a possible new way of moving blocks to the pyramid site. |
