实用英语综合训练与自测。3
2004-7
高等教育
教育部《实用英语》教材编写组编
174
320000
《实用英语:综合训练与自测(第3版)》：权威性：本套教材由教育部规划并推荐使用。编者与审者均是国内知名专家教授及多年从事英语教学的优秀教师。
先进性：本套教材积极吸收了国内外最新外语教学研究成果及教材编写理论，创造了专科层次英语教学的崭新体系。
实用性：本套教材体现了提高学生语言应用能力的宗旨，更密切结合了学生毕业后实际工作的需要。
通用性：本套教材在选材和练习设计上，注意了文、理、工各科知识的相互渗透，兼顾了各专业的需要。
Unit 1
Unit 2
Unit 3
Unit 4
Unit 5
Unit 6
Unit 7
Unit 8
Test 1 (Unit I-Unit 4)
Test 2 (Unit 5-Unit 8)
Test 3 (Unit 1-Unit 8)
Key to Exercises
Key to Tests
If you have ever flown across several tme zones, you must have experienced jet lag You arrived in a new time zone, but your body was still living on the time in the old time zone. You were wide-awake and ready for dinner in the middle of the night, and you wanted to sleep all day. People suffer from jet lag because all living things have a biological clock. Plants and animals are all in rhythm with the natural divisions of time —day and night and the seasons. Some French scientists did an experiment with honeybees. They put out sugar water every morning at 10:00 and at noon, and the bees came to drink the water at exactly the right time. Then the scientists put the sugar water in a room that was brightly lit 24 hours a day. They started putting the sugar water out at 8:00 p.m.It took the bees a week to find it at the different hour, but from then on they came to eat in the evening instead of in the morning. Later the scientists took the honeybees to New York. The bees came for the food at the time their bodies told them, only it was 3:00 p.m.New York time.Their bodies were still on Paris time. Humans, like other animals, have a biological clock that tells us when to sleep and eat.It causes other changes, too. Blood pressure is lower at night, the heartbeat is slower, and the body temperature is a little lower. The honeybees in the experiment reset their biological clock for different feeding hours. Humans do this, too. People who work at night learn to sleep during the day and eat at night. Students who fly halfway across the world to study in another country get used to the new time zone after a few days. Our bodies are controlled by a biological clock, but we can learn to reset it at a different time. ……
