机经内容：

　　话题1：

　　【题目】讨论关于birds anting这一习性的三种解释。

　　阅读要点：

　　【阅读】Demonstrate three theories to explain why birds have the habit.

　　1. Birds use anting to irrigate skin during feather change in summer.

　　2. The acid released during anting by ants can help resist parasites growing on birds.

　　3. Anting is a way for birds to feed on those ants.

　　听力要点：

　　【听力】Refute the three explanations mentioned in reading passage.

　　1. It is just a coincidence between the time of feather change and bird anting.

　　2. Anting cannot reduce the growth of parasites on some birds.

　　3. Birds will have other things to rub themselves, but they do not tend to eat those things.

　　话题2：

　　【题目】讨论健康计划Wellness Programs(即公司推出奖励计划给达到healthy-related goal的员工) 是否对员工有益。

　　阅读要点：

　　【阅读】Wellness Programs in United States bring lots of benefits to companies and employees.

　　1. The programs can become a motivational tool for people to lose weight and quit smoking, bringing much healthier lifestyle.

　　2. Employees will be more inclined to take exercises and have wholesome diets through the motivation of the Wellness Programs.

　　3. Although the program might cost companies a great deal of money at beginning, it saves more compared to the spending for employees’ sickness.

　　听力要点：

　　【听力】The program does not work.

　　1. The program may be an effective way to motivate employees in short term, but it cannot keep for a long period. Research shows that after several years, people are back to their bad habits.

　　2. The program is not fair for every employee, because cases differ. Some who have to take care of their family or cope with chores do not have enough time to exercise, while others are genetically fat.

　　3. Companies might suffer great financial loss in long term, because many employees will not stay in one company forever.

　　话题3：

　　【题目】讨论关于40年前黄腿山蛙数量下降的三种解释。

　　阅读要点：　　【阅读】Demonstrate three theories to explain why the number of yellow-legged mountain frogs declined 40 years ago.

　　1. A kind of fish, the trout, was introduced to this area and the trout ate tadpoles of the frogs.

　　2. The use of pesticides contaminated the habitat.

　　3. The frogs there were infected by a fungal disease.

　　听力要点：

　　【听力】Refute the three explanations mentioned in reading passage.

　　1. The trout was introduced 100 years ago, however the decline happened 40 years ago. The time does not match.

　　2. Rainfall tends to wash the pesticides to lower and farther places. However, frogs lived in areas with higher altitude than that of farms using pesticides.

　　3. Yellow-legged mountain frogs can produce some antibodies within their bodies, so that they can resist to the infection of fungal disease.