单选题You will hear 4 short dialogues. For each dialogue, there is one question and four possible answers. Choose the correct answer—A, B, C, or D. You will hear each dialogue ONLY ONCE.

单选题{{I}} Questions 22～25 are based on the following monologue.{{/I}}

单选题According to the passage, in primitive societies, ______.

单选题IQuestions 11～13 are based on the following dialogue./I

单选题Learning a foreign language means ______.

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单选题The biggest safety threat facing airlines today may not be a terrorist with a gun, but the man with the portable computer in business class. In the last 15 years, pilots have reported well over 100 incidents that could have been caused by electromagnetic interference. The source of this interference remains unconfirmed, but increasingly, experts are pointing the blame at portable electronic devices such as portable computers, radio and cassette players and mobile telephones. RTCA, an organization which advises the aviation industry, has recommended that all airlines ban such devices from being used during "critical" stages of flight, particularly take-off and landing. Some experts have gone further, calling for a total ban during all flights. Currently, rules on using these devices are left up to individual airlines. And although some airlines prohibit passengers from using such equipment during take-off and landing, most are reluctant to enforce a total ban, given that many passengers want to work during flights. The difficulty is predicting how electromagnetic fields might affect an aircraft's computers. Experts know that portable devices emit radiation which affects those wavelengths which aircraft use for navigation and communication. But, because they have not been able to reproduce these effects in a laboratory, they have no way of knowing whether the interference might be dangerous or not. The fact that aircraft may be vulnerable to interference raises the risk that terrorists may use radio systems in order to damage navigation equipment. As a result, loud music sound makes the passenger unable to hear the instructions turning off his radio, this is the most worrying things to airlines.

单选题What is the first word the baby learned to say?

单选题Dangerous forms of waste often are created from the chemicals used for industrial processes. During the past few years, with more places of the world industrialize and more new products are produced, the amount of the chemicals has increased seriously. Each year over 80,000 different kinds of chemicals are used in industries, which produce hundreds of millions of tons of harmful waste around the world. It is very difficult and expensive to eliminate these chemicals or to store them in a particular way that doesn't damage human life and the environment. Harmful waste every year causes many major health problems. However, it is often after some serious event has happened that governments will take actions and cut down the levels of dumped harmful waste. In 1989, a school in New Jersey had to be closed because the students there had suffered too much exposure to chromium(铬). Later it was known that large amounts of chromium had been dumped nearby and blown around the school. Many researches have been done to get information on the effects of different chemical. Since waste chemicals always have been mixed together, it will also be essential to learn what the influence of the combinations of these chemicals is. It has been realized by some government that the problem is very serious. They are trying to make laws to get rid of harmful waste. They are also trying to make limitation on the amount of industries that often release harmful waste. Both the governments and public must contribute to the solution. In order to affect policy makers, they can choose not to buy those products that need the production of harmful waste, and produce less harmful waste themselves. It has been said by many scientists that waste production can be reduced. The waste can be cut down by at least one-third by using existing technologies.

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单选题Whichdaysdoestheman'ssonnotwork?A.Monday,Friday,andSaturday.B.Monday,Wednesday,andFriday.C.Tuesday,Thursday,andSunday.D.SaturdayandSunday.

单选题According to the author, which of the following statements is NOT true about their car-Jaguar?