单选题 Questions19-21 are based on the recording you have just heard.

单选题 Questions17-19 are based on the recording you have just heard.

单选题 Learning is an essential process for living things to acquire necessary skills and behaviors. Scientists have already found that there is a critical period for learning in man and animals. Once the right time for learning a skill or a certain behaviors has passed, this skill or behavior can never be properly learned. That we speak our own language perfectly and the languages we learn later imperfectly also depends on learning this skill at the right time. The brain develops in such a way that it is ready to learn to speak between the ages of about ten months and ten years. Languages learned later are not spoken perfectly. The ability to speak a language is a mixed motor and sensory skill. It is necessary to hear all the sounds, the subtle differences between similar but not identical sounds, the rhythm and tone of the language. One has also to work tongue, throat, and lips to control breathing. All this has to be managed at one and the same time. From some time after birth until the age of six or seven, normal children all learn this perfectly, and without much difficulty they can learn two or even three languages at the same time, without confusing one with the other. But later, most of us cannot acquire this skill. We may learn to write and read the new language perfectly, but to acquire the right accent and the ability to speak so that no one can detect that the language is not our mother tongue hardly ever occurs. But those of us who still want to learn foreign languages after these early milestones have been passed need not worry, for though we may not learn to speak a new language like the natives, we know from thousands of examples that we can go on learning languages beyond the age of eighty. There are so many activities adding up to the simple word 'learning' that although some of the processes become less efficient with ageing of the brain, our actual experience of learning helps us in learning new materials. Normal social and emotional development probably also needs the correct stimulating at the right time. We can observe evidence of this in those rare cases of children who have been completely neglected from birth. Sometimes illegitimate children in the country are put away in barns to conceal their existence from the neighbors. They are taught nothing, not even to be house-trained or to speak. These children then grow up mentally defective. Even if they are found and rescued by the age of four or five, it is too late. Though they can be taught a lot, their speech is always inadequate and their brains never reach the standards of their brothers or sisters.

单选题 Questions6-9 are based on the conversation you have just heard.

单选题 中国的CPI CPI是居民消费价格指数(consumer price index)的简称，可以反映居民购买消费品及服务的价格变动。它不但与人们的生活密切相关，在国家的价格体系中也占有很重要的地位。中国的CPI涵盖居民生活中所消费的食品、服装、医疗和教育等8大类、262种商品和服务的价格。数据来源于全国6.3万个价格调查点，包括超市、专卖店(specialties stores)和农贸市场等。一般来说，CPI的波动直接影响着国家经济调控措施的出台(enactment)与力度，CPI的高低也间接影响股票市场的变化。

单选题 Now listen to the following recording and answer questions19-21.

单选题 Questions10-12 are based on the passage you have just heard.

单选题 Questions20-23 are based on the recording you have just heard.

单选题 Questions2-5 are based on the conversation you have just heard.

单选题 百度(Baidu)是全球最大的中文搜索引擎。2000年1月，李彦宏(Robin Li)和徐勇在北京中关村创立了百度公司，致力于向公众提供“简单、可依赖”的信息获取方式。经过多年的发展，百度已经拥有数千名研发工程师，他们掌握着世界上最为先进的搜索引擎技术。百度已经成为掌握最尖端的核心技术的中国高科技企业之一。百度提供的所有产品操作简单，涉及普通公众工作和生活的各个方面。它已成为中国最受欢迎、影响力最大的中文网站。

单选题 中医(Traditional Chinese Medicine)是中华文化不可分割的一部分，为振兴华夏做出了巨大的贡献。如今，中医和西医(western medicine)在中国的医疗保健领域并驾齐驱。中医以其独特的诊断手法、系统的治疗方式和丰富的典籍材料，备受世界瞩目。中国的中医事业由国家中医药管理局(State Administration of TCM and Pharmacology)负责。现在国家已经出台了管理中医的政策、法令和法规，引导并促进这个新兴产业的研究和开发。在定义上，中医是指导中国传统医药理论和实践的一种医学，它包括中医疗法、中草药(herbology)、针灸(acupuncture)、推拿(massage)和气功(Qigong)。

单选题 Questions12-14 are based on the passage you have just heard.

单选题 Questions13-15 are based on the passage you have just heard.