Chalk used in school classrooms comes in thin sticks. Lessons are often presented to entire classes on chalkboards (or blackboards, as they were originally called) using sticks of chalk. 1.
As found in nature, chalk has been used for drawing since prehistoric times. And it helped to create some of the earliest cave drawings. Later, artists of different countries and styles used chalk mainly for sketches(素描),and some such drawings have survived. 2.The method was to grind(碾碎)natural chalk to a fine powder, then add water, clay, and various dry colors. It was then rolled into stick shape and dried.
3. Class sizes began to increase at that time. Therefore, teachers needed a convenient way of conveying information to many students at one time. Not only did instructors use large blackboards, but students also worked with personal chalkboards, completing with chalk sticks and a sponge or cloth to use as an eraser. These small chalkboards were used for practice, especially among the younger students.
An important change in the nature of classroom chalk brought was in chalkboards. Blackboards used to be black, because they were made from true slate(石板).While some experts advocated a change to yellow chalkboards and dark blue or purple chalk to copy writing on paper, when makers began to shape chalkboards from synthetic(合成的)materials during the 20th century, they chose the color green, arguing that it was easier on the eyes. 4.
Almost all chalk produced today is dustless. Earlier, softer chalk tended to produce a cloud of dust that some feared might contribute to breathing problems.5. It's just that the dust settles faster.
A. Dustless chalk still produces dust.
B. Yellow became the preferred color for chalk.
C. Paper made only from rags at this time was expensive.
D. That's because this method has been proven cheap and easy.
E. Chalk was first formed into sticks for the convenience of artists.
F. Baking chalk longer to harden it more helps to produce less dust.
G. Chalk didn't become standard in schoolrooms until the 19th century.
There’s an ongoing discussion over whether electric vehicles(EVs) should emit sounds to let the blind and other pedestrians know they're on the scene. Some think those sounds should be standardized一like the “beep, beep, beep” of heavy machinery backing up, so you'll think “something heavy this way comes” when you hear it. Several car companies have created their own sounds, especially for car markets outside the United States.
Starting in 2021, all new electric vehicles of any model will need the acoustic vehicle alarming system or AVAS. That sound will come into play when the car is going backwards or when it’s traveling at less than 12 miles an hour—speeds at which cars are more likely to be combined with pedestrians.
“We're calling on the government to take this announcement further by requiring AVAS on all existing electric and hybrid vehicles and to make sure drivers have them switched on, ” John Weisman, guide dog owner and Guide Dogs staff member, said in a statement shared by CNN.
This action followed in the steps of Japan, which was an early adopter, passing its rules in 2010. Meanwhile, the National Highway Traffic Safety Administration passed its final ruling in February 2018, requiring vehicles to emit sound if they’re traveling slower than 6 mph.
Drivers in most situations have the ability to shut off the device when it is needed. They will probably eventually be standardized register “electric car” when you hear it. And that’s a good thing to reduce the mess on the roads.
1.What can we learn about AVAS?
A.Its speed is limited to 12 miles an hour.
B.The Japan government isn’t in favor of it.
C.Not all the newly-produced EVs need to use it.
D.It sounds the alarm when the car is backing up.
2.What is John’s attitude to AVAS?
A.Supportive. B.Cautious. C.Unconcerned. D.Doubtful.
3.What is the last paragraph mainly about?
A.The usage of AVAS. B.The characteristics of AVAS.
C.The benefits of using AVAS. D.The ways of turning off AVAS.
Bob Dylan has won the 2016 Nobel Prize in Literature, announced Sara Danius, Swedish Academy’s permanent secretary, on Thursday in Stockholm.
The Nobel Prize in Literature for 2016 is awarded to Bob Dylan “for having created new poetic expressions within the great American song tradition,” Danius said at the Swedish Academy.
“As an artist, he is versatile; he has been active as painter, actor and scriptwriter,” said the official statement.
Apart from his large production of albums, Dylan has published experimental work. He has written the autobiography Chronicles (2004), which describes memories from the early years in New York and his life at the center of popular culture, it added.
Born on May 24, 1941 in Duluth, Minnesota, in the United States, the 75-year-old rock singer is the first songwriter to win the glorious award and the first American to win since novelist Toni Morrison in 1993.
Barack Obama said the honour was well-deserved. “Congratulations to one of my favourite poets,” he wrote on Twitter.
Dylan, who took his stage name from the poet Dylan Thomas, had long been regarded as a potential prize winner.
Former Poet Laureate Sir Andrew Motion is among those who have ever praised Dylan’s lyrics, saying they are often the best words in the best order.
Dylan began his musical career in Minnesota before heading for New York. Many of his best-known works date from the 1960s, when he became an informal historian of America’s troubles. His songs Blowing in the Wind and The Times They are A-Changing were popular in the anti-war and civil rights movements.
Few experts, though, expected the academy to extend the award to a folk music songwriter. In 112 years, no songwriter has ever won before. What makes a man who has only ever written three books a suitable winner of the Nobel Prize in Literature?
1.What does the underlined word in Para 3 mean?
A.able to do things in different fields
B.able to understand others’ feelings
C.able to produce a lot
D.able to succeed at an old age
2.Many of Bob Dylan’s best-known songs _______________.
A.were written before he arrived in New York.
B.date back to the middle 1970s.
C.were often sung in the political movements.
D.show America’s troubled history.
3.What is the main idea of the passage?
A.Dylan’s winning the Nobel Prize in Literature.
B.Dylan’s life experiences as an artist.
C.Dylan’s contribution to the American literature.
D.Dylan’s musical career in America.
It’s hard to be a bird in a world which is in the charge of mankind.
You can hardly hear yourself sing, let alone hear the songs of your friends… and worst of all, you can’t hear a predator(捕食者). Noise is almost everywhere, especially noise from traffic.
Researchers have tried to study the influence of road noise on animals by looking at animals living near noisy roads.
“We figured out a way to have just the noise without any of the other effects of the road, and to do that we put many speakers in a forest where there was no road,” said Chris McClure, a biologist at Boise State University and The Peregrine Fund. He and his team carried out their experiment at a place popular with birds in Idaho as they fly south for the winter.
While the noise kept lots of birds away, some remained. But they had trouble putting on enough weight to support them in the next part of their migratory journey.
“They have to take food but they also have to avoid getting eaten by a predator. But these two things can’t be done at the same time because to eat, they have to look down, which means they aren’t looking at predators.”
And when it’s too loud, they can’t hear the alarm calls of other birds. So they have to waste time looking for predators instead of searching for food.
By 2050, it’s thought that enough new roads will be built to circle the planet more than 600 times. But there’s an easy solution to the noise problem—“Lowering speed limits does a lot.”
So next time you’re driving through nature, just slow down a little. It’s safer for you and the wildlife. And you can enjoy the view a little longer.
1.Who does the word “you” in Para 2 refer to?
A.A driver. B.A predator. C.A researcher. D.A bird.
2.Why did the researchers do the experiment in a forest without roads?
A.To prevent birds from being hit by cars.
B.To separate noise from other effects of the road.
C.To test a larger number of birds.
D.To put as many speakers as possible.
3.Why can’t birds put on enough weight with much noise around?
A.They can’t concentrate on looking for food.
B.They have to fly south for the winter.
C.They can’t hear the alarm calls.
D.They feel afraid of the noise.
4.What is advised to do to protect birds from the noise problem?
A.To build enough new roads.
B.To carry out more experiments.
C.To enjoy the view a little longer.
D.To drive slowly through nature.
听下面一段独白，回答以下小题。
1.Who is speaking?
A.A student. B.A teacher. C.An actor.
2.What do we know about the young man in Good Will Hunting?
A.He has a gift for math.
B.He is in a top university.
C.He is from a rich neighborhood.
3.Which movie is based on Alice Walker’s novel?
A.Dead Poets Society. B.Schindler’s List. C.The Color Purple.
4.What will the listeners do next?
A.Read a novel. B.Watch a movie. C.Take a class.
听下面一段较长对话，回答以下小题。
1.What day is it today?
A.Friday B.Saturday C.Sunday
2.What is the man doing?
A.Watching TV. B.Doing his homework. C.Making a telephone call.
3.What does the man advise the woman to do?
A.Have a rest. B.Find a quiet place. C.Go to another room.
4.When will the woman probably finish her homework?
A.Later at night. B.Tomorrow morning. C.The day after tomorrow.
