Unit 7

1. Unit 7 The Light of the Twenty-first Century

2. Long before, put sth to use 1. A scientific discovery is often made long before someone is able to put it to use. Long before vs. before long • They arrived at home long before the rain started. • The robbers ran away long before he realized what had happened. • Before long they finished their task. • They were caught in a traffic jam, but before long after it, they arrived at the airport.

3. Put sth to use Put sth to use: start to use sth • When shopping, you’d better buy something you would put to use in real life. • Computers have been put to use in schools since decades ago. • He is going to put his experience to good use in his new job. (He is going to derive profit from his experience.)

4. Use • Come into/get out of use: start/stop being used • Have no use for sb: refuse to tolerate sb; dislike • Have no use for sth: have no purpose for which sth can be used • Make use of sth/sb: use or benefit from sth/sb

5. Occur, coherent 2. But sometimes discovery and invention happen at the same time, as occurred more than thirty years ago with the discovery of coherent light and the invention of the laser.

6. Occur Occur: happen; exist, be found; come into sb • Traffic accidents occur very often nowadays. • Misspelling occurs every page. • The disease occurs most frequently in rural areas. • A good idea suddenly occurred to me. • Does it ever occur to you that you might be able to marry a foreigner? • Occurrence: event, incident, happening

7. Coherent Coherent: (of ideas, thoughts, speech, reasoning, etc) connected logically; be consistent; easy to understand; clear • A coherent analysis, argument, description • The government lacks a coherent economic policy. • Your writing is coherent. • He is not very coherent on the phone. • Coherence • Cohere: (vi.) (Of ideas, reasoning, etc) be connected logically; be consistent

8. Stand for, amplify, stimulate, emit, radiate 3. The word laser stands for “light amplification by stimulated emission of radiation.”

9. Stand for Stand for sth: be an abbreviation of sth; represent sth; be in favor of sth, support • The shortened form ECNU stands for East China Normal University. • What does the letter “M” in Chandler M Bing stand for? • He hates fascism and all it stands for. • The Communist party is a party that stands for racial equality. • Whose opinion will you stand for as you are going to give a speech?

10. Amplification Amplify: increase sth in size or strength; add details to a story, make fuller • Amplify the sound, electric current, signal • Can you amplify your narration? • Amplifier 扬声器，扩音器

11. Stimulated stimulate: make sb or sth more active or alert, arouse sb/sth • Usually praise can stimulate one to make greater efforts. • The exhibition stimulated interest in the artist’s works. • What has stimulated him to work so hard? • Stimulant 兴奋剂，含兴奋剂的饮料；起刺激、激励作用的活动

12. Emission emit: give or send out • The volcano emits smoke, lava and ashes. • She emitted a cry of pain. • The cheese was emitting a strong smell.

13. Radiation radiate: send out rays of light or heat • The room is heated by the warmth radiating from the stove. • Nuclear wastes can sometimes radiate some harmful rays that influence the environment. • Radiation therapy 放射疗法；radiation sickness 辐射病，放射病

14. In contrast, spread out 4. In contrast, incoherent light, like the light from the sun or a light bulb, moves away from its source in all directions, so its strength is very spread out.

15. Contrast In contrast, by contrast, in contrast with/to: • She had almost failed the exam, but her sister, by/in contrast, had done very well. • In contrast with their system, our system is quite old-fashioned. • His white hair was in sharp contrast to his dark skin.

16. Spread out Spread out: (cause sth to) become distributed; extend the surface area, width or length of sth by unfolding or unrolling it • Don’t all sit together, and spread yourselves out. • The bird spread out its wings. • He spread the map out on the floor.

17. Translate 5. In this process, the atoms of a certain substance, such as a crystal or a gas, are excited in such a way that they produce coherent light. A person working with a laser can aim this coherent light, called a laser beam, in any direction. (Translate)

18. Application 6. As soon as the laser was developed, scientists began thinking of practical applications for it. Apply: make a formal request; put or spread sth onto sth; make practical use of sth • You can apply to the headmaster for a key of this teaching building. • The teacher helped the students apply the glue to the surface of posters. • The results of this research can be applied to new developments in technology.

19. Application Application • Keys are available on application to the headmaster. • The board received thousands of applications for the post. • Lotion for external application only, three applications per day • That invention can have a variety of applications in industry.

20. Incision, with no danger of… 7. Laser can be used in surgery to open and close incisions with no danger of infection. With no danger of infection • He knew that he was with no danger of being harshly punished. • With no danger of being drowned, she swam freely. • In danger of extinction, many species have been protected in certain areas.

21. Leave sb/sth behind 8. A laser beam can completely destroy a cancerous growth without leaving behind any dangerous cancer cells that could start a new tumor. • Leave sth/sb behind: fail or forget to bring or take sb/sth; cause signs of one’s actions, an event, etc, to remain

22. Leave sb/sth behind • Wait! Don’t leave me behind. • You can leave your umbrella behind since it won’t rain. • The riot left a trail of destruction behind. • She left the virtue of benevolence behind by helping others all in her life.

23. Discoloration, discolor 9. More recently, lasers have been used to remove skin discolorations like freckles, age spots, and birthmarks. Discolor: change or spoil the color of sth; (of color) change or be spoilt • Smoking discolors the teeth. • My favorite jean trousers discolored after years of use.

24. Enough to…, focus on, trap, slow …down 10. A laser beam can be made narrow enough to focus on a single cell, on part of a cell, or even on individual atoms and molecules. In fact, lasers are now being used to “trap” atoms and slow them down, letting scientists study the ways atoms and molecules move during chemical reactions.

25. Trap Trap: keep sb in a place from which he wants to move but cannot; keep sth in a particular place • He’s trapped in the lift and nervously waiting for someone to help him out. • They were trapped in the burning hotel. • This pajama is made of a special fabric that raps body heat. • She was so young that she was trapped into a marriage of no love at that time. • He was trapped into telling the police all he knew.

26. A variety of…, convert … into… 11. This technique is being used in a variety of research projects—for example, to study how plants convert sunlight into energy through the process of photosynthesis and to take a “snapshot” of the chemical reaction that is the first step in vision, when light hits the retina of the eye.

27. Convert Convert …into…: change sth from one form or use to another • That ancient castle was converted into a prison years after its owner died. • Convert rags into paper, a house into flats, dollars into yens • He’s converted to Catholicism. • conversion, convertible

28. Bring sth to…, be based on… 12. Over the past twenty years, personal computers have brought tremendous changes to the home and the workplace, and many of the most important developments in computer technology are based on lasers. Bring sth to … Be based on …以……为基础

29. Harden, price codes 13. In factories, lasers are used to cut cloth and harden metals. In supermarkets, a laser at the checkout counter reads the price codes on packages. Harden Price codes

30. Make a difference, instead of, sound waves 14. Lasers have also made a big difference in the way telephones work. Instead of changing sound waves to electricity that travels through copper wire, the most modern telephone technology works by changing sound waves into pulses of laser light that travel through hair-thin glass fibers.

31. Make a difference Make a difference: have an effect on sth • Do you think his philosophy can make a difference in our practical life? • Superpowers like the USA try to make a difference in the way the world runs. • What her parents said made no difference in her decision.

32. Lessen, scarce 15. An added benefit is that this technology lessens the need for copper, a scarce and valuable natural resource. Lessen: become less, reduce • The pain was already lessening. • We should lessen the negative impact of human activities on the environment. • The rescue team tried to lessen the likelihood of more deaths or injuries.

33. Frame 1: how to make a complaint Some ways to complain: • It was supposed to have been ready last week. • I was told that it would be ready by now. • I was led to believe that it would be ready in a week. • Is there a reason why it’s not ready? • Is there some problem?

34. Frame 1: how to make a complaint Some excuses: • The parts have ordered, but they haven’t come in yet. • Two of our repair people are out sick. • We’re a little behind schedule at the moment. • Please be patient. We’re doing the best we can.

35. The passive with present perfect verbs • They haven’t fixed my radiator.  My radiator hasn’t been fixed. • We have notified the landlord.  The landlord has been notified.

36. Sense verbs with like, as if, and as though • Your car sounds like a motorboat at full speed. • Your new TV isn’t working right. The picture looks like a snowstorm. • You’re afraid to ride your motorcycle because the engine smells like burning oil. • Your cassette player hasn’t worked right for the last few days. It sounds like a thunderstorm.