1 . The humble beaver (海狸) could hold the key to saving our water, according to a new research at has found how their da m building skills protect the rivers threatened by climate change.

The research, done on the rivers in Colorado, found the wooden banners built by beavers raise water level upstream. As it builds up, the water flows into surrounding soils and secondary waterways. These acts separate out extra nutrients and pollutants before water reenters the main channel downstream.

Extreme weather events, such as severe storms, impact water quality in major river systems. Droughts and floods are becoming more frequent, and the scientists have also found they are contributing to an increase in the American beaver in the US, and consequently an explosion of dam building.

The team chose to monitor a 40-kilometer stretch of the East River. They reviewed data on water levels gathered hourly by sensors fixed in the river and the areas along the river.

They also collected water samples, including from below the ground’s surface to monitor nutrient and pollutant levels. The researchers compared water quality along the stretch during a historically dry year, to water quality the following year when water levels were unusually high. They also compared these year-long datasets to water quality during the nearly three-month period, starting in late July2018, when the beaver dam blocked the river.

The study revealed the dams increased nitrate (硝酸盐) by nearly 50% by increasing the pressure of the water flow upstream 10 times over, which pushed more water out into the surrounding areas. The nitrates are absorbed and digested by tiny organisms in the soil. This helped increase the oxygen content and quality in the rivers.

Beavers’ hard work is responsible for the land they love.

In an age of rapidly growing urbanization, rooftop farming has emerged as a sustainable response     1     the challenge of creating green space in cities. This innovative practice transforms rooftops into mini farms, where vegetables, fruits, and even flowers     2     (plant), providing local residents with fresh produce and adding a touch of nature to urban environments.

Rooftop farming, also     3     (refer) to as vertical agriculture, is more than just a trend; it’s a step towards environmental conservation. Green roofs with vegetation help to absorb sunlight and release moisture, cooling the air and reducing the demand for air conditioning,     4     in turn lessens energy     5     (consume) and carbon emission. Meanwhile, rooftop farms serve as educational platforms,     6     (teach) city dwellers about sustainable agriculture practices and the importance of     7     (local) sourced food.

As urban populations continue to grow, rooftop farming fosters community engagement     8     promotes healthier lifestyles by providing access to fresh and organic produce. When we look towards     9     future where environmental consciousness and sustainable practices become increasingly vital, rooftop farming stands as a testament to our ability to cultivate more than just food—we cultivate hope for a     10     (green) and more resilient (可迅速恢复的) world.

4 . American high school students are terrible writers, and one education reform group thinks it has an answer: robots. Or, more accurately, robot­readers — computers programmed to scan students’ essays and spit out a grade.

Mark Shermis, professor of the College of Education at the University of Akron, is helping to hold a contest, set up by the William and Flora Hewlett Foundation (WFHF), which promises $ 100,000 in prize money to programmers who write the best automated (自动的) grading software. “If you’re a high school teacher and you give a writing task, you’re walking home with 150 essays” Shermis said. “You’re going to need some help.”

Automated essay grading was first proposed in the 1960s, but computers back then were not up to the task. In the late 1990s, as technology improved, several textbooks and testing companies jumped into the field. Today, computers are used to grade essays on South Dakota’s student writing assessments (评价) and a handful of other exams, including the TOEFL test of English fluency, taken by foreign students.

The Hewlett contest aims to show that computers can grade as well as English teachers — only much more quickly and without all that depressing red ink. “Automated essay scoring is objective,” Shermis said. “And it can be done immediately. If students finish an essay at 10 pm, they will get a result at 10:01 pm.”

Take, for instance, the Intelligent Essay Assessor, a web­based tool marketed by Pearson Education, Inc. Within seconds, it can analyze an essay for spelling, grammar, organization, and help students to make revisions. The program scans for key words and analyzes semantic (语义的) patterns, and Pearson claims that it can understand the meaning of text much the same as a human reader.

5 . There’re plenty of fresh fruits and vegetables available in local markets. But while those red juicy strawberries look fresh, consumers have no way of knowing how long the fruit can be stored at home. The same goes for distribution centers and supermarkets.

Now, the food technology startup One Third, located in the Netherlands, is looking to change that with an infrared (红外线) scanner that can accurately predict how long fresh fruits and vegetables will last. The startup is named One Third because one-third of food is wasted due to spoilage (变质) every year.

The startup’s founders were inspired by a UK company that uses this type of technology in the medical field and decided to see if it was applicable for food. “I looked at the challenges in the food-supply chain and found out that 40 percent of food waste is fresh produce. One of the biggest causes of waste is that nobody knows shelf life.” founder and CEO of One Third, Marco Snickers said.

Quality inspections at farms and distribution centers are done manually (手动地). An inspector checks the fruits and vegetables and makes notes about the size and quality. Then the food is sent to consumers without considering travel time or how long the produce will remain usable.

Using the infrared scanner at the distribution center means that inspectors can use the information to approve shipments that will ensure the produce can be distributed on a timely basis. This means that a shipment of ripe tomatoes will not be sent long distances away.

One Third’s scanner combınes the technology of optical scanners, image modeling, and Artificial Intelligence to provide accurate shelf-life predictions.

The startup found that the technology can reduce up to 25 percent produce waste that was caused by spoilage. “Global food waste has an enormous environmental impact, reducing global food waste cuts global greenhouse gas emissions and promotes global food security,” said Jacob Smith, a climate expert from the University of Maine.

8 . What is a GPA?

A GPA, or Grade Point Average, typically ranging from one to four, is a number reflecting your course performance on average. It’s used by universities to determine whether students meet academic standards and by students to enhance job prospects or secure admission into post-graduate programs.

How to calculate a GPA?

● Determine the letter grade and the number of credit hours for each course you take in a term;

● Translate the letter grade to grade points using your school’s grading system;

● Multiply the grade points by the credit hours for that course;

● Add up all the credit hours for the courses;

● Divide the total number of grade points by the total credit hours and you get the GPA.

What are the consequences of failing college courses?

● Every failing grade (F) significantly impacts your GPA for that academic year, limiting clubs, organizations and program choices, as competitive programs require top GPAs.

● Most financial aid programs require a specific GPA. A sharp drop in GPA due to several course failures may lead to withdrawal from financial aid programs, unless you retake the courses and pass.

● For college athletes on sports scholarships, failing courses repeatedly can lead to losing scholarships and team sports.

● Failing multiple courses can result in school removal and affect future applications.

In many Asian, African and Latin American cultures,     1     (extend) eye contact is impolite and it is thought of     2     an offensive or a challenge of authority. It is considered politer to have brief eye contact, especially between people of different social status (like a student and a teacher, or a child and his elder relatives). For example, if a Japanese woman avoids looking someone in the eye, she is not showing a lack of interest nor is     3     (she) showing a lack of confidence. Instead, she     4     (be) polite, respectful and appropriate according to her culture. So in many of these cultures, you should take care of     5     kind of eye contact you initiate with those who are your     6     (superior) or in authority over you, so that you are not thought to be     7     (respect) or rude. As you can see, it is vital for you to know what eye contact communicates before you visit a new culture.

Before you travel, you can either look up relevant information in your local public library     8     check out a book about the culture of the country you plan to visit in a bookstore. Learn how to make use of eye contact and other body language     9     (flexible) so that you     10     (perceive) to be polite, and so that you can better connect with people who are foreign to you!