Wood has many great characteristics that make it the perfect building material.It is cheap，durable，easily available，and most importantly，environmentally sustainable.The one thing it is not，is transparent! Now thanks to a team of scientists at Stockholm’s KTH Royal Institute of Technology the material may even be able to add that feature to its already impressive list.
Lead researcher Dr，Lars Berglund said he was inspired to create the transparent wood after learning how Japanese researchers had developed a see-through paper for use in flexible display screens for electronic devices.The team began by pulling out the wood’s lignin(木质素).The lignin-free wood was then dipped into a polymer(聚合物)and baked at a temperature of 158°F for four hours.The result was a hybrid product that was not only stronger and lighter than the original wood but also，almost transparent.The researchers were able to adjust the level of transparency by varying the amount of the polymer injected and also by changing the thickness of the wood.
While scientists have previously created a see-through wood for small-scale applications like computer chips，the transparent wood is the first one being considered for large scale applications.The researchers，who revealed their findings in Biomacromolecules on April 11，picture using the transparent wood in buildings to allow for more natural light，or to create windows that let in the desired amount of light without sacrificing privacy.
Wood that allows light to pass through could lead to a brighter future for homes and buildings.Berglund also thinks the wood could play a significant role in the design of solar panels.The semitransparent material would be able to keep light longer and give it more time to interact with the conductor，thus resulting in better solar efficiency.Additionally，substituting the currently used glass with this new product would help solar energy manufacturers improve their carbon footprint and lower the cost.They are now experimenting with ways to scale up the manufacturing process so that the transparent material is cost-effective to make and easy to use.
1.What does the underlined part“that feature”in Paragraph 1 refer to?
A. Cheap. B. Durable. C. Sustainable. D. Transparent.
2.Which of the following correctly shows the process in which the transparent wood is made?
①Dip the wood into a polymer. ②Adjust the amount of the polymer.
③Make the wood lignin-free. ④Bake the wood for some time.
A. ③→①→④→② B. ③→①→②→④
C. ①→②→③→④ D. ④→③→②→①
3.Which of the following is true according to the text?
A. Berglund got the idea of transparent wood while making paper.
B. Varying the amount of the polymer changes the wood’s hardness.
C. The transparent wood would be used only for homes and buildings.
D. The cost of making the transparent wood still needs to be cut down.
4.What is the last paragraph mainly about?
A. The bright future of the transparent wood.
B. The wood’s role in the design of solar panels.
C. The disadvantages of the currently used glass.
D. Solar energy manufacturers’carbon footprint.
Hadi Partovi，founder of Code.org believes every student should learn the basics of computer science just like they do math，physics，or biology，regardless of what they want to do in the future.The expert says knowledge about the subject is important to understand how the world around us works and compares it to learning about photosynthesis(光合作用)，even though not every student is going to be a botanist.To spark students’interest，he created the“Hour of Code，”which introduces the world of computing to anyone，from ages 14 to 104，in a fun，interactive manner.Observed annually during Computer Science Week，the event now draws tens of millions of kids from over 180 countries.
The“Hour of Code”，which can be scheduled anytime during Computer Science Week，begins with an introductory video on computer science.Participants can then select from hundreds of fun assignments that are sorted by both grade level and coding experience.Though each project is designed to last just sixty minutes，beginners can deal with as many challenges as they desire.
To help introduce computer science in classrooms on a more regular basis，Code.org has also developed a catalog of online courses that can be incorporated(纳入)in a school’s regular curriculum.Since the nonprofit began offering the courses in 2013，over 704，000 teachers have signed up to teach introductory computer science to over 22 million students worldwide.
Thanks to the efforts of the pioneer，about 40 percent of US schools now offer computer science as a subject.The numbers are even higher—an impressive 70 percent—if after-school offerings such as robotics clubs are included.Even more encouraging，eight years ago，just 19，390 students took an Advanced Placement Computer Science exam.By the spring of 2017，the number had jumped 415 percent to 99，868.
1.Why did Hardi Partovi create the“Hour of Code”?
A. To train computer scientists for the future.
B. To introduce the world of computing to teachers.
C. To add a programme to Computer Science Week.
D. To help people learn computer science in a fun way.
2.The“Hour of Code”is so called most probably because___________.
A. it is observed annually
B. it can be scheduled anytime
C. its projects last sixty minutes each
D. its tasks can be sorted by coding experience
3.What do we know about Code.org’s online courses?
A. Schools can use them regularly in their classrooms.
B. They help the developer make lots of money.
C. Over 704，000 teachers have been learning them.
D. They have existed for over 10 years up to now.
4.What do the numbers show in the last paragraph?
A. The efforts of Hadi Partovi.
B. The influence of robotics clubs.
C. The effect of Hadi Partovi’s efforts.
D. The development of many US schools.
A crew of six teenage girls completed a nine-day sailing trip in the US recently，after braving seasickness and strong winds.
For the past three years，the Sea Cadet teenagers who set sail were all male.Roger Noakes，who captained the boat，said this was the first time he’d taken out an all-female crew.
The girls asked for an a11-girls trip in August this year.The crew set sail along with three adults，Noakes and two Sea Cadet representatives.The original plan was for the girls to sail 24 hours a day in rotating shifts(轮流换班)along the coast and then return.Things turned out differently，however. “The first night was rough because the wind was really hard.The waves were going up and down，”said Abby Fairchild，16.“Everybody got seasick.”Noakes gave the girls the option of just sailing in the bay and not going into open water.“But they decided they were going.”
The teenagers then sailed a long way overnight and slept in shifts.“We’ve learned everything from steering(掌舵)the boat itself to putting up the sails to cooking while we have rough seas，”said 15-year-old Olivia Wilcox.
The teenagers stopped on land in Massachusetts.They didn’t make it to their original destination in Maine，where they were supposed to have a celebratory dinner，due to the weather and winds.They said they weren’t disappointed，however，as they’d learned a lot.“They learned about boating，and above all，they built confidence and character，”said Noakes.
1.What was special about the US Sea Cadet trip this year?
A. It was the longest sailing trip ever.
B. It was the first all-female-crew sailing trip.
C. It was the most dangerous sailing trip ever.
D. It was the first sailing trip for teenagers.
2.What happened on the crew’s first day of the trip?
A. They all got seasick.
B. They regretted taking the trip.
C. They decided to stay in the bay.
D. Some of them were injured.
3.Which of the following best describes these young sailors?
A. Determined and cooperative. B. Hard-working and talented.
C. Understanding and creative. D. Adventurous and skillful.
4.According to Noakes，what was the sailors’greatest benefit from the trip?
A. They acquired excellent sailing skills.
B. They learned to work in teams.
C. They built confidence and character.
D. They knew the sea better.
Outdoor Science Field Trips!
1.Which trip caters for more age groups than all the others?
A. Habitat & Home B. Only Rain Down the Drain
C. healthy earth healthy bodies D. Rockin’and Recycling
2.What will you learn from Only Rain Down the Drain?
A. Information about weather. B. Knowledge about water systems.
C. Grade specific science standards. D. Stories about Sonoma County.
3.Which trip should you choose if you want to learn to forecast the weather?
A. Habitat & Home B. Only Rain Down the Drain
C. Rockin’and Recycling D. Weather or not
听下面一段独白，回答以下小题。
1.How long did the speaker stay in the South Corinth School?
A. 1 year. B. 2 years. C. 3 years.
2.Who is the coolest teacher in the Corinth High School?
A. Mr Nolan. B. Mrs Jackson. C. Mr Best.
3.What is the speaker’s attitude towards her teachers?
A. Thankful_
B. Disappointed.
C. Interested
听下面一段较长对话，回答以下小题。
1.How long have the man and the woman been looking for an apartment?
A. 1 month. B. 3 months. C. 6 months.
2.How much is the rent of the apartment for a year?
A. 2，000 dollars. B. 12，000 dollars. C. 24，000 dollars.
3.What kind of apartment does the woman prefer?
A. A downstairs apartment.
B. An apartment with few neighbors.
C. An apartment that allows keeping pets.
4.What does the woman think of the apartment on Main Street?
A. The most appropriate.
B. Too expensive and noisy.
C. Too far away from her office.
