3 . Many of the Earth's creatures die because of humans' choices. These choices have nothing to do with food or shelter or anything else that helps humans survive. What kills millions of animals all over the world is that humans want to make money by doing so.

People use parts of animals for everything from hats to handbags, from jewelry to ashtrays and to make powders that supposedly improve a person's life. Deciding that a species is endangered and protecting it by law are not always enough. People who kill wildlife illegally rarely get caught.

During the late 1980s, saving elephants became a popular cause. Wildlife protection groups made sure everyone saw pictures or films of elephants with their faces cut off for their ivory. These groups also proved that certain populations of elephants were decreasing. As a result, most people stopped buying objects made of ivory. Laws against poaching (偷猎) were made stronger. Many countries made importing ivory illegal. Killing elephants for their Ivory became more risky and less profitable (有利可图的).

However, concern for certain species will become weak after a while. In the late 1970s, people protested (抗议) against the killing of seal babies. Everyone was shocked to see young seals being killed in their icy habitat. The cruel activity stopped. But ten years later, the number of seal babies killed was higher than ever.

Other animal protection movements have come and gone, such as saving the whales and protecting dolphins. The whale population appears to have increased for now. And the laws are finally changed in America to protect the dolphins that swim with tuna fish in parts of the Pacific Ocean.

In the years to come, people's attention will probably turn to some other endangered species. Plenty of them urgently need attention. During this time, will the elephants be forgotten?

Every Setback Is a Test for Us

Hello, everyone. I’m Li Jin Today I am very glad to have the chance to speak about the topic: Every Setback Is a Test for Us.

Thanks, for your Listening.

6 . Confused by food nutrition labels? You’re not alone. Now, researchers have suggested an alternative: labelling the amount and type of exercise needed to burn off the calories.

Current food and drink labels display nutritional information such as the amount of calories and fat. However, researchers led by Prof. Amanda Daley at Loughborough University say that these labels are having a limited effect on changing buying habits. Instead, they propose a labelling system called ‘physical activity calorie equivalent or expenditure’ (PACE) (体育活动热量当量), which shows how many minutes or miles of physical activity are needed to burn off the calories. For example, a small bar of milk chocolate contains 230 calories, which would take about 42 minutes of walking, or 22 minutes of running, to burn off.

They pooled the data from 14 previous studies which compared the impact of PACE labelling with that of other types of food labelling, or with no food labelling at all. They calculated that PACE labelling could cut a person’s daily calorie intake by up to 200 calories. “Public health agencies may want to consider the possibility of including policies to promote PACE food labelling as a strategy that contributes to the prevention and treatment of obesity (肥胖) and related diseases,” said the researchers.

The UK’s Royal Society for Public Health has already called for PACE labelling to replace the current system. However, not everyone is convinced. A spokesperson for the eating disorder charity Beat said: “We believe that anti-obesity campaigns that focus on weight instead of health are ineffective and that recommending more exercise is an ineffective and over-simplistic approach to a complex problem. Most urgently, public health campaigns must consider people’s mental as well as their physical health, moving from obesity-shaming to evidence-based campaigns that build confidence and support healthy eating.”

8 . In all the world's cultures, people sing, play instruments, and celebrate with music. It plays such an important role in our lives that all fields focus on its study, including one looking at the biology of music. Experts find that because of the way our brains process music, learning to play an instrument or just listening to music can have a wide range of benefits.   

Music education has received a lot of attention. Learning to play an instrument can help children improve math, science, and language skills. One study in Canada tracked children's IQ scores for nine months, discovering that children who studied music had the biggest test score improvements. The secret may lie in the way reading music and playing notes use several areas of the brain, increasing our ability to learn school subjects. For example, reading notes improves spatial (空间的) reasoning skills, which are helpful in solving math problems like fractions (分数).   

Music is also used for medical purposes, such as the treatment of diseases which affect memories. The secret lies in the way the brain processes music. One area near the forehead, the medial prefrontal cortex(脑前额叶外皮), connects music with memories stored in two other areas: the amygdale(杏仁核) and hippocampus(海马体). That's why an old song can remind you of something that happened years ago. For patients suffering from diseases like Alzheimer's, listening to music can help unlock buried memories by strengthening musical pathways to memories.   

With the evidence of music's benefits, it's no wonder some countries make music study a part of their education systems. People are recognizing that more than just a form of entertainment, music is also great for the brain.