【推荐2】Vegetable displays have become surprisingly similar in markets around the world, which offer primarily commercial vegetables such as tomato, eggplant, onion, carrot, beet, lettuce and broccoli. In other words, world diets are actually becoming more similar and based on fewer crops.

A much greater diversity of vegetables exist in traditional food systems, but many of these crops are poorly integrated in current markets and diets. A total of 1,097 vegetable species, with a great variety of uses and growth forms, are cultivated worldwide. Still, we only seem to be familiar with less than 7% of these species.

The diversity of vegetables is more than a local preference. It could play an important role in ensuring adequate levels of nutrition and in meeting the challenges of agricultural production posed by climate change and soil degradation (退化). Many traditional vegetables are known to have higher nutritional value than commercial vegetables, and are well-adapted to local conditions, exhibiting resistance to drought, pests, diseases and poor soil conditions. For example, the Mayan spinach (玛雅菠菜) contains exceptional levels of protein, vitamin C and iron, and provides leaves year-round with little water and in poor soil conditions. Traditional crops like this could be strategic in helping more people meet the recommended levels of fruit and vegetable consumption, which is currently n global health concern.

Lack of information on traditional vegetables is a major barrier to their use and promotion because it prevents a wider recognition of their values and understanding of how best to grow, process and market them. Organizations around the world are placing increasing efforts on promoting these so called “forgotten foods”, because of their value and potential in bringing nutrition and income benefits to consumers and producers, as well as in strengthening local food traditions. This could be the beginning of a great transformation towards more diverse, vegetable-rich food systems around the world.

【推荐1】According to a survey published by the American Institutes for Research last year, a total of 57 colleges were operating some form of CBE programs and about 85 percent of all the higher education officials said they were either designing a CBE program at their school or were considering doing so.

Students in a CBE program choose a central field of study, just as they would at a traditional college or university. Yet instead of attending a series of classes led by professors or teaching assistants at schools, the students study online and direct themselves.

CBE programs require students to show their understanding of a given set of sills Students must prove their mastery of skills that relate to their field of choice by taking related exams. Once they have met all the requirements of their study programs, the students will get their degrees.

CBE programs have made use of many new technologies, especially internet and online media. This helps reduce barriers for nontraditional and other students by bringing higher education to them. And programs that permit students to work at their own speed may save students' money by reducing the time it takes for them to earn a degree.

But some educators have concerns about the value of the education that CBE programs offer. Johann Neem at Western Washington University argues that the purpose of higher education is not simply to help students master certain skills. It should teach students how to think critically (批判性地) understand the subjects they are studying more deeply and see how they are connected to other subjects. Only that way can they put the knowledge to better use.

He said, “You need to explore, think .. get shaken, have a conversation and struggle. And those things take time.”

Instead of supporting CBE, he adds, policy makers and educators should look for ways to improve access and reduce costs for traditional higher education.

【推荐2】More than ever before, students all over the world are turning to online learning to further their education.     1     In order to help you as an online learner develop better study skills, keep reading to see some of the best study tips.

Practice Good Time Management. Time management is possibly one of the most important and valuable skills for online learners.     2     If you are busy with online studies as well as other commitments, avoid a study session right before an exam. It’s recommended that you plan ahead and be responsible for your own time.

Remove Distractions. This might be a hard step to conquer. From social media to kids playing in the next room, you’re bound to face countless amounts of distractions. The best advice is to try your best to lessen all the distractions and stay focused! Of course, distractions are unique to each individual and may also depend on circumstances.     3    

Build Your Network. Many online courses are developed around the concept of cooperation with professors and educators who encourage students to work together to achieve their end goals. This is why it is important to build as many relationships as possible not only with your peers but with professors too.     4     Don’t be afraid to create a virtual study group either.

Create A Dedicated Study Space.     5     You needn’t recreate a proper university lecture room. Instead set up a study space to which you dedicate (致力） your studies to. Whether it’s in your own home or at the local library, it doesn’t really matter. What is important is that you create a space that is not only quiet but will be effective as well.

【推荐3】Tyson Terry wakes up, gets ready for school, and then turns on his computer. Ifs his first day of seventh grade. But he’s not going anywhere. Nowadays, going to school has become unsafe for him and many other students around the world.

For many students, distance learning has become the usual state. They have to take classes on virtual platforms (虚拟平台). Besides, kids are also stuck at home during their free time. Tyson and his friends can chat with each other only on screens.

A recent study shows that Tyson and his friends aren’t the only young people getting plenty of screen time these days. In April 2020, almost 1,500 parents in Canada reported their kids had less exercise and more screen time. Researchers have found that kids who spend a lot of time on screens are more likely to have eye problems and trouble with reading. Yet right now, screens are the only safe way to learn or socialize. How should they get out of this dilemma (困境)?

“I think to say screen time is bad or good is both dangerous,” says Michelle Guerrero who studies diseases. Different types of screen time have both costs and advantages, she says. You should be mindful of how much screen time you get. But for many families, “right now, staying within two hours is just not realistic.”

Taren Sanders, a health scientist, agrees. “Overall, I’m not too concerned about the additional screen time kids are having,” he says. The things you should be thinking about are the amount of exercise you get and the way you spend your free time.

The biggest problem with screens is that people usually sit without moving while they watch screens. A long time sitting leads to bad changes in one’s body and is more likely to cause health problems. So an important question to ask yourself is not how much screen time you are getting, but how active you are.