It is not a secret {#blank#}1{#/blank#} trees are vital to our life. They provide us with food, wood and most {#blank#}2{#/blank#} (important), oxygen. Now there is one more thing we can add to this list—blocking out harmful bacteria from water.

    The discovery {#blank#}3{#/blank#} (make) by a team {#blank#}4{#/blank#} (consist) of scientists from the Massachusetts Institute of Technology (MIT) and high school students {#blank#}5{#/blank#} were seeking a natural water filter(过滤)—one that would help communities in developing countries that do not have {#blank#}6{#/blank#} (accessible) to modern water filter systems.

    The {#blank#}7{#/blank#} (research), led by Professor Rohit Karnik, decided to turn{#blank#}8{#/blank#} trees for help, because they could allow liquid to flow through, while blocking out air bubbles.

    They began by cutting 1.5-inch-wide sections of tree bark from the branches of a white pine tree. The people related then tested the wood's filtering ability by pouring water containing red dye particles of different sizes through. To their {#blank#}9{#/blank#} (amaze), they found that it was effective in trapping all the particles. Greatly {#blank#}10{#/blank#} (encourage), the team conducted another experiment, this time with water that contained bacteria. Sure enough, the sapwood held back 99% of the bacteria, allowing only 1% to flow through.

    Do you have any idea of New Year paintings?{#blank#}1{#/blank#} (know) as “paper paintings” and “painted pictures”, New Year paintings are a special art form in Chinese folk culture. Without New Year paintings, our traditional Chinese folk culture would be much less {#blank#}2{#/blank#}(color). The paintings get such a name because they are {#blank#}3{#/blank#}(most) posted during the Chinese New Year holiday for {#blank#}4{#/blank#}(decorate) and they are also accepted as a symbol of New Year's greetings.

    New Year paintings appeared around the Tang dynasty, replacing the previous door pictures believed to be able to protect the residents and drive away ghosts. In the Song dynasty the New Year paintings{#blank#}5{#/blank#} (create) on a large scale(规模){#blank#}6{#/blank#} the printing techniques improving, the content and forms of New Year paintings became various. The development of the paintings matured in the Ming and Qing dynasties,{#blank#}7{#/blank#} the art hit its heyday (全盛期).

    There are many {#blank#}8{#/blank#}(tradition) printing methods of New Year paintings,{#blank#}9{#/blank#} (include) woodblock printing, stone-block printing, offset printing, watercolor painting, etc.{#blank#}10{#/blank#} is reported, woodblock-printed New Year paintings are the most popular and interesting ones, according to a recent survey.

    My American friend kindly invited me to her home to celebrate this year's Thanksgiving Day. I {#blank#}1{#/blank#} (experience) my first ever Thanksgiving.

    On that day, we watched the Thanksgiving parade (游行) in New York City on TV. My friend's family sat{#blank#}2{#/blank#}front of the television. They came from all over the States and enjoyed being together{#blank#}3{#/blank#} (look) at their happy faces, I thought it was really a holiday for families, just like the Mid-Autumn Festival in China.

    That evening, we had a big Thanksgiving dinner. This {#blank#}4{#/blank#}(tradition) meal includes roast turkey, mashed potatoes and assorted vegetables. When the dishes and plates arrived at the table, we started to take{#blank#}5{#/blank#} (turn) to say the things we were {#blank#}6{#/blank#}(thank) for. This, in fact, is a Thanksgiving tradition many families practice in the US.

    Then, the food {#blank#}7{#/blank#}(pass) around the table and we all ate far too much. I also had desserts with my dinner. There{#blank#}8{#/blank#}(be) different kinds of pies, such as apple pies, pumpkin pies and coconut pies.

    If one mentions Thanksgiving, one must talk about Black Friday, the Friday {#blank#}9{#/blank#}follows Thanksgiving Day. Shops across the United States will give their {#blank#}10{#/blank#}(big) sales of the whole year on Black Friday. Many people go crazy about it. I saw many long queues outside the shops on that day.

    My experience of teaching students was a wonderful adventure. I had to deal with various challenges again and again.

    The {#blank#}1{#/blank#} (great) part of it was the relationship I developed with two students. One of the students was Michael, {#blank#}2{#/blank#} I met when I was working for a kindergarten. Before I became a morning bus assistant, I {#blank#}3{#/blank#} (hear) that Michael was a student who would always shout, stand up on the bus, make fun {#blank#}4{#/blank#} other students, and distract the bus driver. So I decided that each morning, {#blank#}5{#/blank#} he got on the bus, I'd have Michael sit beside me. At first he didn't like this idea. But soon he settled down, {#blank#}6{#/blank#} (know) he had no choice. I began to talk to him about little things outside of school life, such as his weekend {#blank#}7{#/blank#} (activity) and things that he liked to do. I also listened {#blank#}8{#/blank#} (close) to him. As I gave Michael the attention that he needed, little by little, he began to behave better and better.

    Another student I took a special interest in was a boy {#blank#}9{#/blank#} (name) Tony, a third grader. To some degree, Tony seemed to be a slow or passive learner. So I decided to see if I could find a way to encourage Tony {#blank#}10{#/blank#} (stay) at the task. Before long, he was paying more attention to his studies and scored high in all tests.

    Generally speaking, a motto is a short and suggestive {#blank#}1{#/blank#} (express) of a guiding principle, {#blank#}2{#/blank#} can inspire people to work for self-betterment. My motto is "God helps those who help {#blank#}3{#/blank#} (they)". Sometimes I am lazy and don't want to work, {#blank#}4{#/blank#} the moment I think of my motto I will become {#blank#}5{#/blank#} (energy) again and devote myself to {#blank#}6{#/blank#} I am doing. I write my motto where I can see it {#blank#}7{#/blank#} (easy). Every time {#blank#}8{#/blank#} (face) with difficulty, I will {#blank#}9{#/blank#} (inspire) with much confidence by the sight of my motto. My motto also makes me become {#blank#}10{#/blank#} independent person. My friends, what is your motto?