1 . Clean water might not grow on trees, but the trees might do the next best thing—provide a cheap and easy way of filtering (过滤) it.
Researchers from the Massachusetts Institute of Technology (MIT) have been able to use wood from tree branches to filter water both in the laboratory and in the field. Compared to other water filters, the new way of filtering water gets an edge. This could provide an inexpensive and low-tech alternative to costly methods of getting clean water in places that need it the most.
In a new study, researchers show that the natural structure of wood from non-flowering plants like pine provides enough filtration to remove bacteria from water. This method was already proven to work in a lab in 2014, but now the researchers have found, through interviews with potential users and tests of local water sources, that the tree-based purification system works just as well in the field in India and that the locals are willing to use it.
The branches of non-flowering plants are built of thin, straw-like tubes called x ylem in the layer of wood under the skin. The unique structure of the xylem tissue in the branches allows it to work as a water filter because these channels are connected to each other through porous membranes (多孔薄膜). These membranes can catch water pollutants, similar to a water filter membrane.
The researchers were even able to extend the shelf life of dry wood filters to around two years by dipping (浸泡) them in a protective mix of hot water and ethanol (乙醇). To make this potentially life-saving technology be reachable to those who need it, the construction of the filter is open to the public and instructions can be found on their website detailing how anyone can try to construct their own wood water filter.
1. What does the underlined “gets an edge” in Paragraph 2 probably mean?| A．Has a limitation. | B．Has an advantage. |
| C．Faces a challenge. | D．Produces an effect. |
| A．To call on people to protect local water sources. |
| B．To show the consequences of lacking pure water. |
| C．To explain why water filters are in great demand. |
| D．To prove the water filter is effective and welcomed. |
| A．They are thinner than other plants' branches. |
| B．They have wide straw-like tubes in the xylem tissue. |
| C．The tiny holes of membranes can trap water pollutants. |
| D．The layer of wood under their skin carries plenty of water. |
| A．A unique way of obtaining water from plants. |
| B．The working principle of tree-based water filters. |
| C．MIT creates a high-tech water purification system. |
| D．MIT's wooden water filter comes into practical use. |
It took a day’s drive, but distance was beside the point. I always enjoyed long journeys in my father’s car with my family. However, things went different that time. We were moving to a new town, not for any tourist destination, but to settle down, for my father had a new job there. My mother, sitting on the passenger seat in the front, was talking with my father. She looked excited for the coming new life. But I was down, feeling nervous about starting a new school life. Entering a new school meant adapting to a completely different environment and meeting new classmates and teachers, which I was not good at.
On my first day at the new school, I felt lost and out of place. The students already knew each other well, and they chatted happily during breaks. I missed my old friends terribly and wished I could go back to my old school. Feeling lonely. I often spent time alone during breaks and after classes, reading books in the library or drawing pictures in the art room. I missed the good days I had with my old friends and longed for that sense of belonging.
As the days went by, I still found it hard to fit in. I was shy and found it difficult to strike up conversations with my classmates. Some of the kids in my class noticed my discomfort and tried to be friendly, but I couldn’t shake off the feeling of being an outsider. I only had words with my desk mate, Alex, when necessary. Things took a turn for the worse when I knocked off Alex’s water bottle by accident, although I picked up the bottle immediately and apologized to him. He got mad at me and seemed not to forgive me. Soon I found we were avoiding each other.
注意：1. 续写词数应为150左右；
2. 请按如下格式在答题卡的相应位置作答.
However, I was assigned to pair up with Alex to design a poster.
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________Alex proudly introduced that the fantastic picture was drawn by me.
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