One day, gardeners might not just hear the buzz of bees among their flowers, but the whirr of robots, too. Scientists have managed to turn an unassuming drone (无人机) into a remote-controlled pollinator (授粉媒介) by attaching horsehairs coated with a special, sticky gel to its underbelly.
Animal pollinators are needed for the reproduction of 90% of flowering plants and one third of human food crops. Chief among those are bees — but many bee populations in the United States have been in steep decline in recent decades. Thus, the decline of bees isn't just worrisome because it could disrupt ecosystems, but also because it could disrupt agriculture and economy. People have been trying to come up with replacement techniques, but none of them are especially effective yet.
Scientists have thought about using drones, but they haven't figured out how to make free-flying robot insects that can rely on their own power source without being attached to a wire. “It’s very tough work,” said senior author Eijiro Miyako, a chemist at the National Institute of Advanced Industrial Science and Technology. His particular contribution to the field involves a gel, one he’d considered a mistake 10 years before and stuck in a storage cabinet. When it was rediscovered a decade later, it hadn’t dried up or degraded at all. “I was so surprised because it still had high viscosity,” Miyako said.
The chemist noticed that when dropped, the gel absorbed an impressive amount of dust from the floor. Miyako realized this material could be very useful for picking up pollen (花粉). He and his colleagues chose a drone and attached horsehairs to its smooth surface to mimic a bee’s fuzzy body. They coated those horsehairs in the gel, and then controlled the drones over lilies, where they would pick up the pollen from one flower and then deposit the pollen at another one, thus fertilizing it.
The scientists looked at the hairs under a scanning electron microscope and counted up the pollen grains attached to the surface and found that the drones whose horsehairs had been coated with the gel had about 10 times more pollen than those that had not been coated with the gel.
Miyako does not think such drones would replace bees altogether, but could simply help bees with their pollinating duties. There’s a lot of work to be done before that's a reality, however. Small drones will need to become more controllable and energy efficient, as well as smarter, with better GPS and artificial intelligence.
1.What does the underlined word “viscosity” in Para.3 probably mean?
A.Hardness. B.Stickiness.
C.Flexibility. D.Purity.
2.We can learn from the passage that ______.
A.bees disrupt both agriculture and economy
B.scientists have invented self-powered robot insects
C.bees in the United States are on the edge of extinction
D.Miyako found the special feature of the gel by chance
3.A drone works best in picking up pollen when ______.
A.its body is made like a bee’s
B.its GPS works more efficiently
C.some flowers are coated with the gel
D.horsehairs with the gel are attached to it
4.According to Eijiro Miyako, the drones ______.
A.are not yet ready for practical use
B.may eventually replace bees in the future
C.are much more efficient than bee pollinators
D.can provide a solution to economic depression
My Grandpa Forgets Who I Am
A few days ago I visited my grandfather in hospital. He has Alzhemier’s-a degenerative disease that usually starts slowly and gets worse over time. I thought I was prepared to see him. I knew chances were slim that he’d actually recognize me.
He didn’t. As a matter of fact, he had no idea that he even had grandchildren. But he was excited that somebody came to visit him. I tried to explain to him who I was. But after he told me multiple times that he didn’t have grandchildren, I gave up. And my heart broke into a million little pieces.
I was tired of explaining things to him. So I just smiled. He smiled back. It’s a genuine smile. Like a long time ago, when he’d take me by the hand and made this big world a little bit less scary for me. Now I have to take his hand.
We sat in silence for a little while, before he told me to call my grandma. This was the first time I had tried so hard to hold back tears. My grandma died four years ago and he didn’t remember. He thought she was stuck on her way to pick him up.
My grandpa used to be a strong, hard-working man. He was the person you turned to when you needed your car fixed, your tires changed or something heavy to be carried. Sadly, that man left this world a long time ago, and left behind a man that is lost and scared.
I want to help him. I want to make him feel better. I want to tell him about his old life, and how great it was. So I sat with him and I held his hand, and every once in a while I told him how good he looked and how much I liked the color of his shirt and how it brought out the blue in his eyes. I told him that my grandma was on her way whenever he asked about her, and I made sure the glass in his hand was always filled with water.
I can’t take away his pain. I can’t help him remember. I can’t make the disease go away. All I can do is hold on to the memories-hold on for both of us.
1.When the author first saw her grandpa in hospital, ________________.
A.she gave up on him B.they were both excited
C.he didn’t recognize her D.they talked about the past
2.The author was close to tears because ________________.
A.grandma died about four years ago
B.grandpa needed to be taken care of
C.grandma didn’t make it to the hospital
D.grandpa believed grandma was still alive
3.Which of the following best describe the author?
A.Tolerant and merciful. B.Considerate and patient.
C.Warm-hearted and grateful. D.Strong-minded and generous.
4.The author wrote this passage to _________________.
A.show pity towards her grandpa B.record memories of her grandpa
C.express deep love for her grandpa D.call on further study on Alzheimer’s
Hands-on activities can enrich a trip by creating fond memories and instilling knowledge about the local culture through interactivity.In Japan,a wide range of activities are offered to tourists at single workshops,many open air museums,as well as craft villages across Japan.
Fruit picking
Typical duration:30 to 60 minutes
Typical price range:800 to 3000 yen
Many farms across Japan offer fruit picking opportunities to tourists.The common procedure is for the visitor to get charged for a certain time period during which he/she can pick and enjoy the fruits on the spot.Typical fruit available for this activity include strawberries,apples and grapes.
Cheese/butter making
Typical duration:40 to 60 minutes
Typical price range:600 to 1000 yen
Cheese and dairy products are commonly made in northern Japan,especially in Hokkaido.Some farms offer cheese and butter making workshops.Visitors usually learn how to make the product and consume it on the spot.The Furano Cheese Factory is one place that offers such workshops.
Washi paper
Typical duration:30 to 60 minutes
Typical price range:500 to 1000 yen
In many workshops,for example at one near Ainokura Village,tourists can experience how washi paper is made.At other establishments,such as the Kyoto Museum of Traditional Crafts and Takumi no Sato,it is possible to make crafts such as fans and lanterns using washi Paper.
Tatami making
Typical duration:About two hours
Typical price range:500 to 1000 yen
It's possible to try Tatami making at many places in Japan including Otaru and Hakone.Tatami mats are made of straw and measure roughly 180 cm×90 cm.Few establishments offer workshops whereby you can make a small piece of Tatami and take it home as a souvenir.
1.Which of the following activities takes the longest time? ______
A.Fruit picking. B.Cheese/butter making.
C.Washi paper. D.Tatami making.
2.Where can visitors make dairy products? ______
A.In Hokkaido. B.Near Ainokura Village.
C.In the Kyoto Museum. D.In Otaru and Hakone.
3.What can we infer about hands-on activities from the text? ______
A.Visitors can take part in the activities for free.
B.People can take home the end products as souvenirs.
C.They all involve actually doing a particular thing.
D.They can offer people rich culture about their hometown.
听下面一段独白,回答以下小题。
1.How long will the writing remain perfectly clear?
A.At least 3 days. B.About 20 minutes. C.Less than 10 minutes.
2.What can make the writing disappear more quickly?
A.Chemicals. B.Light. C.Heat.
3.What can we learn about the newly invented paper?
A.It can be used up to 20 times.
B.It might make ink widely used.
C.It will replace the ordinary paper.
听下面一段较长对话,回答以下小题。
1.How did the man learn to skateboard?
A.He had a few lessons. B.He practiced by video. C.His cousin taught him.
2.Where does the man want to skateboard most?
A.By the beach. B.At a city square. C.On a basketball court
3.What does the man say about keeping fit?
A.He finds it hard to work in the gym. B.He has changed his training routine.
C.He should skateboard more often.
4.What does the man advise young people taking up skateboarding to do?
A.Focus on a small number of moves.
B.Buy a cheap board to begin with.
C.Have plenty of patience.
听下面一段较长对话,回答以下小题。
1.What made the woman dissatisfied with the T-shit?
A.The name of the store on it. B.The stain on it. C.The size.
2.Why can’t the woman return the T-shirt?
A.She has worn it B.It was bought too long ago. C.There is nothing wrong with it.
3.What does the woman do at last?
A.Keep the T-shirt. B.Pay extra for the belt. C.Exchange the T-shirt for another one.