第10单元 · 四档阅读与填词

A small radio can play without a battery. Its long antenna catches energy from waves sent by a station. The waves make electricity move inside the set. The set uses this energy to make a quiet sound. We can hear it best in a calm room.

Inside the set, each electron moves from side to side. Together, they form the electric current that passes through the set. Another part chooses one station and keeps out the others.

The wave from that station carries a voice or music. A small part called a diode sends the flow mainly one way. The flow moves a thin piece inside an earphone, and the moving piece makes sound.

The set creates no new energy of its own. All the energy came from the station in the first place. The set catches and changes only a very small share of the wave. That share can make a quiet sound, though it cannot make a loud one.

The Happy Prince is a statue covered with gold. A red gemstone is on his sword, while blue gemstones are in his eyes. From high above the city, he can see poor families. One evening, a Swallow rests at his feet and feels drops of water fall from the Prince's eyes. The Prince is sad about the people below.

The Prince asks the bird to carry the red gemstone to a poor mother with a sick child. The bird plans to fly south, but he sees that the Prince is kind and stays for one more night. This is their first good deed together.

The Swallow later carries the blue gemstones and gold to other people. With each trip, he trusts the Prince more. Their kindness brings food and help to dark streets. The two become a kind-hearted pair.

Winter kills the bird, and the Prince's heart breaks. City leaders throw both away when the statue no longer looks rich. In the story, an angel chooses them as the two best things in the city because of their gifts.

Before a shop sends a package, a worker gets the box ready. The worker packs the things inside and closes it. Then the worker puts a clear address label on the box. If the label falls off, mail workers may not know where to take the box.

A customer may ask the service to email news about the box. These messages show where it has been. They cannot give mail workers the missing address. If the box cannot go on or come back, it may go to the Mail Recovery Center.

Workers there may open a box if the things inside are worth more than 25 dollars. They first look for a name or address. It may be on a smaller packet inside the box.

If workers find an address, they send the box on or return it. If they cannot find one, the things may be given away, used again, thrown away or sold. The search may fail. Even so, it gives the box one more chance to reach the right person.

At Howard and Ninth Streets in San Francisco, pedestrians cross a five-lane road. A fixed signal follows the same schedule even when someone moves slowly. If a person is still walking across the road when vehicles are due to start, a few extra seconds can matter.

During the PedSafe project, engineers tested a video detector at this crossing. A camera watched the crosswalk and predicted whether a pedestrian would still be in the road at the end of the normal phase. If so, the system could hold the signal for up to three more seconds.

The crucial change was responsiveness. Instead of giving extra time on every cycle, the detector could respond to the position of a person who needed it. In that limited sense, the timing could reflect what was happening at the crossing rather than rely entirely on a fixed plan.

A sensible mechanism, however, is not proof of impact. FHWA compared behaviour, waiting time and vehicle movement across several measures and sites, and the wider results were mixed. For officials at a crossroads—expand the idea, revise it or stop—the report offered a useful rule: measure the result before assuming success.

For its Trailblazing display, the Smithsonian built two reader-rail prototypes. They interpreted a display case about mule mail in the Grand Canyon. The rails included braille, raised text, a tactile floor plan and a model of a mule mail train. Buttons played audio descriptions of nearby objects.

Then visitors who were blind or had low vision tested the design. They liked the tactile models, but the speakers sounded muffled in a busy gallery. The team replaced them with handsets and audio jacks.

Other details changed too. Descriptions became shorter, the floor plan moved to a more natural position, and braille text was lined up with the buttons. A second test suggested a flexible playback mode, including pause and rewind. Visitors also wanted audio controls in a consistent place across panels.

The project shows that modern access design grows through careful testing with real visitors. Its strength lies in flexibility: build a prototype, listen to users, and improve the points where access breaks down. The appropriate solution was not simply the newest device; it was the change that answered an observed problem in that gallery.

McConnell Air Force Base in Kansas lies along a major monarch migration corridor. A monarch butterfly may travel south along this route. Its long flight depends on a chain of stops with nectar and milkweed. Much of the base, however, had been covered by short, non-native grass that offered pollinators little food or shelter.

In 2016, the U.S. Fish and Wildlife Service began working with base staff on selected areas. They planted native flowers and milkweed, using local seed when possible. They also replaced several formal flower beds with orderly native plantings that suited a working air base.

The changes needed to solve practical problems as well as provide habitat. Deep roots can hold soil, and dense stems can slow stormwater during heavy rain. Native areas may also need less mowing than short turf. These benefits helped staff see the plantings as part of land management, not an obstacle to it.

The report records monarchs in planted milkweed areas and describes rain gardens that reduce water entering drains. Those observations show that insects used the site and that the landscape handled water differently; they do not prove recovery across the whole migration route. Continued care at McConnell across seasons still matters.

In a language course, silence after a teacher's question can feel like a mistake. A 2017 study treated it as data. Researchers recorded one postgraduate second-language class in Britain for nine hours, then examined who spoke next, how long each turn lasted and whether talk followed the usual teacher-student-teacher pattern.

During some longer pauses, students began a turn or extended a reply before the teacher evaluated it. The class temporarily moved away from the familiar pattern of teacher initiation, student response and teacher feedback. The shift changed who could shape the exchange, although it did not appear in every moment or become permanent.

A separate study asked learners to describe situations when they felt most and least willing to communicate. Its 97 positive accounts and 84 negative accounts connected willingness with several conditions, including wait time, correction, topic and teacher support. These were reports of particular moments, not a controlled test of one classroom technique. Taken together, the studies still leave open whether a fixed pause itself increases participation, because topic, correction and teacher support may change at the same time.

A stronger experiment could compare two groups following the same curriculum. In one, teachers would announce an explicit rule: wait three seconds before anyone replies. In the other, teachers would give no fixed instruction and let each pause carry the implicit message that the floor was still open. Researchers could count how often students began a turn, how long they spoke and whether they extended a reply before teacher feedback. Those measures address the question raised by both studies: does a fixed pause change participation? Keeping the course content and observation method the same would make the comparison easier to interpret.

At the start of A Christmas Carol, the firm of Scrooge and Marley still carries both names, although Marley has been dead for seven years. Scrooge treats warmth, celebration and requests for charity as interruptions to business. The counting-house is the small part of reality he has chosen to notice.

Marley's ghost breaks that order. His chains confirm that a life devoted only to profit has brought punishment rather than peace, and he warns that three spirits will follow. For Scrooge, the visit is unwelcome confirmation that his tidy business world cannot explain everything he sees.

The first spirit returns Scrooge to his lonely childhood and to Fezziwig's generous party. The second shows the Cratchits sharing a small Christmas dinner while money is short and Tiny Tim is ill. The scene is realistic: affection does not make hardship disappear. Scrooge begins to realise that both can occupy the same room.

The final spirit shows a death that causes little grief and a neglected grave bearing Scrooge's name. Scrooge begs to change the future. Generosity may require sacrifice, but the vision makes the cost of refusing every human claim much harder to ignore.

Dickens tests the change after Scrooge wakes. He sends food to the Cratchits, gives to charity, raises Bob's pay and continues to behave differently. Memory supplied sympathy, the present widened his attention, and the future supplied fear; his later actions turn those feelings into evidence.

In April 2023, a report on Dartford's Orchard Theatre described defects in roof panels made from reinforced autoclaved aerated concrete (RAAC) as not significant and proposed replacement over the medium to long term. A routine inspection in September changed the timetable. A specialist found deterioration and recommended immediate closure, so the council had to suspend performances.

The suspension affected more than the stage. Official statements linked the theatre with jobs, nearby businesses and the town's cultural life. They announced plans for continuity, but gave no final repair bill. Readers could therefore see why the council wanted to act without knowing exactly how expensive the roof work would be or how much it would spend overall.

The council and theatre operator announced Orchard West, a temporary venue only yards from the main building. The fully enclosed structure would have 1,000 seats, backstage and front-of-house areas, indoor toilets, bars, heating, cooling and access facilities. Opening it for the holiday programme could keep staff working and bring audiences back to a lively town centre while engineers repaired the roof.

Orchard West was an adequate bridge, not an identical replacement. It could compensate for the loss of a stage by providing another performance space, but it could not remove every inconvenience or the eventual expense of repairing the main theatre. Safety required an immediate stop; cultural continuity required a temporary place to begin again.

H. G. Wells's The Star begins on the first days of a new year. Observatories report that the planet Neptune is moving strangely, but the public barely notices. A wandering body then strikes Neptune and creates a brilliant new star. It grows larger in the winter sky, turning a scientific puzzle into something visible from streets, ships and fields.

A mathematician calculates that the burning body will swing past Earth on its way towards the Sun. He predicts earthquakes, volcanic eruptions, storms, floods and rising heat. Some people pray or leave for high ground, yet ordinary routines continue and newspapers offer reassurance. Wells lets warning and habit occupy the same page until the approaching light can no longer be ignored.

The star never hits Earth. Its heat and gravity are enough to produce disaster. Snow and ice melt; rivers overflow; coasts flood; cities fall in earthquakes. Around the equator, heat, smoke and water make escape difficult, while people elsewhere crowd towards mountains or open sea. At night the world becomes as bright as summer moonlight, an image that is beautiful only until its consequences arrive.

After the star passes, the story briefly describes hotter days, altered motion of the Moon and green land in places once locked in ice. Survivors move towards the poles. Wells is not presenting a climate model: he compresses many physical changes into a catastrophe and then moves on. The point is how completely a familiar world can change even when the planet keeps its general shape.

That shape matters in the final paragraph. Martian astronomers see continents and seas still in place and conclude that Earth suffered surprisingly little damage. From their distance, the event appears mild; they cannot see ruined cities or individual grief. Their report is accurate at one scale and radically incomplete at another. Wells ends by making the reader hold both views at once.

AquaCrop is a free model developed by the Food and Agriculture Organization of the United Nations (FAO) that estimates how water affects the yield of herbaceous crops. Users can compare an attainable harvest with an observed one or examine irrigation schedules during drought. The results can inform planning, although the software does not manage a field or allocate water by itself.

Before a simulation begins, farmers still decide when to plough a field and when to sow. They also decide how much space to leave along each row. A user represents such choices with data about climate, soil, crop and management. The model can then compare possible consequences. It cannot perform the work or decide whether the entered description fits a particular farm.

That fit matters because AquaCrop simplifies the world it represents. It treats a field as uniform and models water moving mainly up and down through rainfall, irrigation, evaporation and related flows. Any result is dependent on these assumptions. Its apparent precision can hide this dependence when a real field varies across slopes, soil patches or management zones.

FAO has also paired the tool with practical instruction. Its event record lists five regional workshops with UN-Water partners in Burkina Faso, China, Egypt, Iran and South Africa. A follow-up workshop in Indonesia brought together case studies from different agro-climatic conditions. Moving from regional practice to shared case studies allowed users to compare how local conditions shaped their use of the same model.

When a calculation is done, users still have to judge the inputs and the question it answered. AquaCrop can make the effects of selected water and management choices easier to compare. It does not decide whether those choices are affordable, fair or practical in a particular place. The numerical result is most useful as evidence within a decision, not as the decision itself.

Mission: Iconic Reefs is a long-term effort to restore seven sites in the Florida Keys. Teams raise coral fragments so they can survive, grow and return to reefs, and the programme also considers animals that control algae. A simple planting total records useful work. By itself, however, it cannot show whether the wider reef ecology is recovering.

Researchers from the U.S. National Oceanic and Atmospheric Administration (NOAA) therefore return to the sites after planting. Divers take overlapping photographs and turn them into two- and three-dimensional models. Ground-control points connect image measurements with depth and location. Across restored and unrestored areas, researchers can compare coral size, condition, health, survival, density and distribution, along with changes in algae, sponges and other organisms.

Environmental sensors supply another layer of evidence. Buoys at four sites collect near-real-time measurements of pH, temperature and wave energy. Rising carbon dioxide changes ocean chemistry, while heat and waves can affect whether transplanted corals live. The sensor record describes the physical environment around a biological change; it does not by itself prove what caused that change.

The two monitoring systems also work on different clocks. Repeat image surveys reveal how colonies and reef communities change between visits. Buoys record daily and seasonal conditions between those surveys. When a later image shows weaker coral growth, the environmental record can help researchers ask whether unusual heat, acidity or wave energy coincided with that period.

Managers must still decide how to divide effort between further planting and continued measurement. Planting expands the area with a chance to recover. Monitoring shows which fragments persist, how the community changes and what conditions accompanied those changes. The balance may shift as evidence accumulates, but a restoration programme needs both action and a credible way to judge its results.