Scientists have recently discovered that Andean condors (秀鹫)— some of the world’s largest birds——barely flap their wings at all while flying. Instead, they use rising air currents to remain in the air for hours.
The Andean condor is the world’s largest soaring bird. They can weigh up to 15 kilograms. Their wings, when spread out, measure up to three meters. Their main food source is the meat of large animals which have died. Soaring high in the sky allows condors to easily spot possible meals on the ground.
Scientists worked together to study the flight patterns of these huge birds and how much effort the birds use when flying. To study the birds while they were in the sky, the researchers attached special devices which could record every beat of their wings.
The scientists learned that most of the condors’ flapping— over 75%— came when the birds were taking off. Once in the sky, the birds flew for very long periods of time without flapping at all. In fact, they only flapped their wings for 1% of the time they were in the air. One bird flew for over five hours without flapping, covering nearly 117miles.
Soaring without flapping is important because birds burn energy every time they flap their wings.
The birds’ soaring isn’t magic. They use the fact that hot air rises to keep themselves up. As hot air rises, it often creates “thermals”— currents of warm air moving upward. The condors soar by making use of these thermals. The tricky part is finding thermals and moving between them.
When birds are forced to land and take off again often, it costs them a lot of energy. The researchers learned that to avoid having to land, the condors did most of their non-take-off flapping when they were closer to the ground and looking for a new thermal.
The scientists reported that even though all of the condors they studied were young, they knew well how to take advantage of the air currents.
1. What can we learn about the Andean condor from the text?| A．They live mairly on small animals. |
| B．Their wingspan is at least three meters. |
| C．They rely on hot air to remain high in the sky. |
| D．They are the birds with the strongest flying ability. |
| A．To measure how far they could fly without flapping. |
| B．To keep track of how often they flapped while flying. |
| C．To calculate the energy required for their flight. |
| D．To confirm their flight patterns. |
| A．Hunting for food. | B．Flying in the sky. |
| C．Getting off the ground. | D．Landing on the ground. |
| A．Condors flap the most when looking for a new thermal. |
| B．No condor can fly for more than five hours without flapping. |
| C．Condors don’t need to look for thermals when soaring in the sky. |
| D．Soaring by using thermals is probably a natural ability of condors. |
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【推荐1】Box jellyfish (箱型水母) are the most poisonous marine animals known to man. They measure 3 meters long and weigh up to 2 kilograms. They are pale blue and transparent in color, and get their name from the cube-like shape of their body. Box jellyfish have 6 eyes on all 4 sides of their body, although it is uncertain how they process what they see as they do not have a central nervous system. They also have up to 15 tentacles (触须) growing from each corner of their body that have about 5,000 stinging (带刺的) cells each.
Box jellyfish can be found primarily in the coastal waters off Northern Australia as well as throughout the Indo-Pacific. They prefer to live at river mouths. They do not have any organs to breathe, and will sleep on the ocean floor from 3 p.m. to dawn. Unlike other jellyfish that merely move along with the current, box jellyfish have developed a way to travel wherever they want to go. They will shoot themselves in a jet-like fashion, reaching speeds of up to 7.4 kilometers per hour.
The diet of box jellyfish consists of thing like fish, small animals, and even other jellyfish. They use their venom, a chemical which causes heart, skin, and breath failure, to kill their prey. Since box jellyfish have eyes, some scientists believe that they actively hunt their prey, holding the belief that box jellyfish have developed a special set of eyes similar to humans that help them skillfully avoid obstacles in the ocean, while others insist that they are just passive opportunists that will wait and catch anything that wanders into their tentacles.
Box jellyfish are responsible for more human deaths in Australia than snakes, sharks, and salt-water crocodiles combined. It is best to avoid them as most stings will result in death. Hopefully, humans and box jellyfish can find a way to live with one another while keeping conflicts to a bare minimum. After all, such a unique species of jellyfish deserves to live and grow just as humans do.
1. Which of the following is NOT mentioned about box jellyfish from the first paragraph?| A．Its size. | B．Its poisonousness. | C．Its color. | D．Its hardness. |
| A．They live in the deep sea in groups. |
| B．They can breathe on the ocean floor. |
| C．They can decide the direction in which they move. |
| D．They usually move along with the current. |
| A．box jellyfish | B．scientists |
| C．box jellyfish’s prey | D．box jellyfish’s tentacles |
| A．To introduce some poisonous animals. |
| B．To describe a kind of animal under the sea. |
| C．To illustrate scientists’ research into box jellyfish. |
| D．To show the relationship between humans and jellyfish. |
【推荐2】I saw my first tree today. Dad used to tell me stories about the trees that still existed when he was a boy. There weren’t very many even then, with the urbanization program in full swing.
The O’Brien home was one of the few examples of old-style wooden structures that hadn’t been destroyed in Boston’s urban-renewal campaign. The family had been able to avoid this because of its wealth and political influence, and the house was passed on through generations to the present. Old man O’Brien had no children, so when he died, the Urban Center bought it. Then an official discovered that the house had a backyard-in the yard was a live tree!
When the news of the tree’s discovery leaked out, quite a few sightseers stopped by to have a look at it, and the local government, realizing the money-making potential, began charging admission and advertising the place. By now it had become a favorite spot for family trips like ours.
Dad paid the fee and we walked through a doorway hidden in a bookshelf and into the backyard. I just couldn’t help noticing the tree!
It was located at one end of the yard, with a fence around it for protection. It was similar in form to the plastic trees I’d seen, but there was much more. You could see details more delicate than in any artificially made plant. And it was alive. But best of all was the smell-fresh, living smell, unfamiliar to the world outside with metal, plastic, and glass. I wanted to touch the bark, but the fence prevented me from doing so.
On the way back, I read through the brochures. One part said the O’Brien home would be torn down next year to make room for some insurance building, and the tree will have to go, too.
I just sat still, fingering the object in my pocket that I had picked in the O’Brien’s backyard. I think it’s called an acorn (橡子).
1. Why could the tree in the O’Brien’s backyard survive till today?| A．It possessed some special characteristics. |
| B．It had a very strong fence around to protect it. |
| C．It was preserved together with the house by its owner. |
| D．It got the local government’s attention as a tourist attraction. |
| A．Annoyed. | B．Calm. | C．Excited. | D．Upset. |
| A．Social progress and urbanization come at a cost. |
| B．Social progress should give way to nature protection. |
| C．Humans value nature protection over social progress. |
| D．Urbanization has more advantages than disadvantages. |
【推荐3】Chimps live in a male-dominated society, where most of their valuable partners are other males. However, as young male chimps become adults, they continue to maintain tight bonds with their mothers, a new study finds.
“The dramatic changes of adolescence are difficult for chimps, just like they are for humans,” says Elizabeth Lonsdorf, an expert on primates (灵长动物) at Franklin&Marshall College who was not involved in the study. “Sure enough,” she adds, “their moms remain a key social partner during this time.”
Previous research has shown chimp mothers provide their sons with support that goes far beyond nursing. Young male chimps that are close with their moms grow bigger and have a greater chance of survival. What’s more, losing their mothers after weaning (断奶), but before age 12，gets in the way of the ability of young chimps to win other males and reproduce.
To see whether this bond extends later into life, researchers followed 29 adolescent (9 to 15 years old) and young adult (16 to 20 years old) male chimps at a research site in Kibale National Park in Uganda and observed them from a distance for 3 years. The team found that the young adult males spent less time with their mothers than the adolescents did—26% vs. 76%. As the male chimps grew older and more independent, they began to travel over wider ranges and spent more time away from their moms.
However, when these young adult males happened to be in the company of their mothers, they acted just like the adolescents. They groomed (梳理) their moms just as often and kept track of them. “Many mothers remained the males’ ‘best friends’ or ‘social partners’ they associated with most frequently,” says study co-leader Rachna Reddy from Harvard University.
Such persistent ties are also common in humans after sons leave their mothers and live on their own—especially in tough times, Reddy says. “We really feel what it’s like to not be able to see our mothers when we want to in tough times. The importance of those bonds in our lives and the comfort we get from them have deep evolutionary roots.”
1. What do we know about Elizabeth Lonsdorf?| A．She is in favor of the new study’s finding. |
| B．She played a supporting role in the new study. |
| C．She did a different study on chimps’ adolescence before. |
| D．She thinks chimps actually live in a female-dominated society. |
| A．It may be easier for it to produce babies. |
| B．It may be easier for it to interact with other chimps. |
| C．It may be tough for it to defeat other males. |
| D．It may be much more aggressive than other males. |
| A．They took care of some motherless chimps. |
| B．They recorded the chimps’ social interaction. |
| C．They worked hard to win the chimps’ trust. |
| D．They limited the chimps’ range of movement. |
| A．To stress the purpose of the study. | B．To improve humans’ mother-son relationship. |
| C．To call on us to protect chimps. | D．To emphasize the significance of the study. |
【推荐1】Humans are not the animal kingdom’s only super fans of fashion. Tits (山雀) can be fashion-victims, too, apparently. A study, published in Behavioral Ecology and Sociobiology by Sonja Wild and Lucy Aplin, shows that, given the chance, they decorate their nests with this season’s must-have color.
Dr Wild and Dr Aplin were following up work published in 1934 by Henry Smith Williams, an American naturalist. He noticed that when he put various colored balls of wool out in his garden, almost always one and only one became popular that season, integrated into local birds’ nests. But which particular color was favored varied from season to season. This suggested that the color chosen by one of the early birds was spotted and copied by others.
Williams’s work was, however, forgotten until Dr Wild and Dr Aplin came across it while following up on a different study. The study noted that, during any given breeding (繁殖) season, the blue tits they were investigating tended to integrate the same herbal plants into their nests regardless of how abundant those herbs actually were. This, too, suggested fashion-following-and it likewise led Dr Wild and Dr Aplin to infer that birds were studying the nests of others and copying them. They therefore set out to rerun Williams’s experiment, but this time to collect some actual numbers.
The birds they followed were part of a well-monitored population of blue, great and marsh tits in a wood near the institute. Of the 68 tits ‘nests built that season in the experimental areas, 26 contained wool, including 18 of the color of wool chosen by the first nest builder.
Tits, then, do seem to be “on trend” when it comes to nest-building materials. Why that should happen remains unclear. Dr Wild and Dr Aplin suspect the trendsetters are older birds, and younger ones simply follow. Williams’s original work, though, suggests such initial choices are random. A bit like those of the leaders of human fashions.
1. What do we know about tits from the first two paragraphs?| A．Tits choose the same color all the time. |
| B．Tits suffer a lot from following fashion. |
| C．Tits tend to copy others in building their nests. |
| D．Tits like to follow fellow birds’ behavior in most cases. |
| A．To offer guidance for William. |
| B．To study birds’ nests. |
| C．To prove birds’ modelling behavior. |
| D．To investigate bird breeding. |
| A．They believed older tits chose colors at random. |
| B．They knew exactly why tits followed the first nest builder. |
| C．They discovered most tits used wool in building their nests. |
| D．They assumed older tits were the ones to lead the trend. |
| A．Tits: Fashion Followers |
| B．Nest Building: Colors First |
| C．Birds: Human Followers |
| D．Scientific Research: Numbers First |
【推荐2】Today’s the day of a big test at school, and you feel awful.
When you’re taking a test, you might feel “butterflies”, a stomachache, or a tension headache. Some people might feel shaky, sweaty, or feel their hearts beating quickly as they wait for the test to be given out
Sound familiar?
Of course, if you didn’t study for the test, you might be worried. That kind of anxiety isn’t as easy to deal with because even if you find a way to calm down, you still might not know what the right answers are.
| A．You’re not alone |
| B．Surely you have test anxiety |
| C．If you are not well prepared for the exam |
| D．You stomach hurts and you have a headache |
| E．Test anxiety is actually a type of performance anxiety |
| F．When you are prepared for a test and you get a handle on your anxiety |
| G．A student with really strong test anxiety may even feel like he or she might pass out or throw up |
【推荐3】The health benefits of gardening
Someone argues that it wastes trouble and time to plant and grow things just for some vegetables and flowers. However, it offers us a lot.
It’s a fun workout. It’s wonderful to get out in the garden on a beautiful day. Planting seeds, pulling up weeds and other gardening tasks actually provide a whole-body workout for adults over 65 years old.
It sharpens your mind.
It benefits your heart and weight. Gardening can contribute to reducing the risk of a heart attack by 30 percent. That is because “playing in the dirt” helps reduce stress. In addition, one goal of doing exercises is to stay in shape.
| A．It lifts your spirit. |
| B．It is a professional practice. |
| C．Gardening can help achieve it. |
| D．Gardening provides a workout for your brain. |
| E．Young children, even adults, enjoy playing in the dirt. |
| F．Even better, whatever your age, it is an activity with a potential harvest. |
| G．Working in a garden can improve your immune system, helping you stay fit. |
【推荐1】Here are three financial habits you might want to consider breaking.
1. Spending more than you want to earn rewards points
Provided they’re used responsibly, rewards credit cards can be a good thing. However, if you find yourself using a credit card just to get more points, you might be in for a world of trouble. One way you can break this bad habit is to only use your rewards card for regular, monthly expenses. Let’s say you decide to leave your card at home and only use it to make payments on your phone bill, which you then pay back in full every month.
2. Ignoring your bills
Coming home to a big pile of bills is a drag. There’s no doubt about it. But tossing them onto the coffee table and ignoring them for weeks on end can have terrible consequences for your financial well-being. Whenever you find yourself faced with a bill, do with it immediately. While it might be a bit of a struggle at first, over time you can get the rewards of having less financial stress.
3. Cycling your debt without fixing the real problem
While having a lower interest rate can help solve short-term problems for you, you could be avoiding the fundamental issue. In fact, it might even be keeping you from coming to terms with the behaviour that is forcing you into a state of debt. Building a budget(预算) could help you uncover ways to cut back and save.
For most of us, changing our behaviour isn’t as simple as turning off a switch, so it may take a lot of time and effort. Starting is the hardest part but, I can assure(保证) you—it gets easier with time.
1. You will get into trouble by using credit cards if you want to .| A．use them to pay your phone bill | B．put your credit cards at home |
| C．pay back in full every month | D．earn more rewards points |
| A．They need to plan their expenses properly. | B．They need to make a lot of effort. |
| C．They need to spend less each time. | D．They need to leave cards in the stores. |
| A．Impossible. | B．Simple. |
| C．Difficult. | D．Unbelievable. |
【推荐2】Weeds compete for soil nutrients, water, space, and sunlight with the crops farmers grow to help feed people. Now a third—generation weeding robot, armed with lasers and powered by Al, offers a perfect labor—saving device.
Trundling(移动)down a row of crops, a battery of twelve cameras scan the ground, identifying weeds through machine—leaning and killing them with a CO2 laser. CO2 lasers use reactions between nitrogen, carbon, and oxygen to generate powerful beams of light that are concentrated through mirrors inside the laser.
The Autonomous Weeder by Carbon Robotics can root out 100,000 weeds per hour, and clear 15—20 acres in a single day—numbers that require a person working an entire season to match. The robot’s onboard supercomputer ensures millimeter precision with its laser so as to avoid accidently clipping(剪掉)crops.
“This is one of the most creative and valuable technologies that I’ve seen as a farmer,” said James Johnson of Carzalia Farm in a statement, who has used Carbon Robotics’ technology on his farm. “I expect the robots to go mainstream because of how effectively they address some of farming’s most critical issues, including the overuse of chemicals, process efficiency, and labor. The sky is the limit.” It’s no surprise that the 2021 model of the Autonomous Weeder has already sold out, even considering its price tag which was quoted at “hundreds of thousands of dollars.”
The de-weeding method of the robot is Certified Organic and in line with regenerative farming practices. Cost—effective weed control is the biggest barrier to entry with organic farming, and agriculturalists looking to make the switch finally have an alternative to help them get their vegetables out to people.
1. Which part of the weeder helps clear grass precisely?| A．The CO2 laser. | B．The battery of cameras. |
| C．Mirrors inside the laser. | D．The onboard supercomputer. |
| A．The robots won’t spread widely. |
| B．The invention is very promising. |
| C．The weeder addresses limited issues. |
| D．The technology needs further improvement. |
| A．Flexible. | B．Affordable. | C．Energy—saving. | D．Environment—friendly. |
| A．It contributes to a higher output. | B．It helps develop organic farming. |
| C．It will replace humans in farming. | D．It isn’t accepted by agriculturalists. |
【推荐3】Orange Unified School District
Quick Reference Guide for Lockdowns
This information is provided as a guideline for actions in the event of a lockdown. Always remember that the first priority is the safety and protection of life.
Lockdowns
A lockdown is the act of keeping students and personnel in a secured location until an emergency or threat is over. You may be required to lockdown your room or facility when a dangerous person or situation is present on or near your site.
Activating a Lockdown:
● A lockdown may be ordered by a principal, site administrator or Student & Community Services (SCS).
● Staff should direct students inside to the nearest room. Do a verbal and visual sweep as you lockdown to get everyone inside.
● If possible, report your attendance, including any extra people in your room, to the office.
● Staff should lock all doors and windows leading to your room. Close all window coverings.
● All students and staff should remain away from doors and windows. If you hear gunfire or someone trying to enter your room, instruct all students and staff to “Drop, Cover and Hold” under desks.
● Under no circumstances will students or staff open a door or window once it has been secured until the lockdown is officially over. When the lockdown is over the “All Clear signal will sound.”
Deactivating a Lockdown:
● A lockdown will be deactivated by the site administrator or Student & Community Services with an “All Clear” signal (which may be an announcement, bell signal etc., to be determined by site administrator).
● All students and staff should return to their assigned rooms or workstations. Staff should account for all students and inform the principal or site administrator of anybody missing.
● The site administrator will assign staff to walk the campus or workplace to ensure that everyone is aware of the deactivation.
1. What can we learn from the passage about a lockdown?| A．It is security measure in the event of a threat. |
| B．It stands for the end of an emergency of threat. |
| C．It means locking a dangerous person in the room. |
| D．It is meant to protect the facilities in an emergency. |
| A．can’t open a door or window unless they are sure there is no danger |
| B．need to stay near doors and windows to wait for further instruction |
| C．must report to the office how many people there are in the room |
| D．should try to make sure that no one is left outside |
| A．Any staff member. | B．Site administrator. |
| C．School principal. | D．Heard of the students’ union. |
