相关习题
 0  139335  139343  139349  139353  139359  139361  139365  139371  139373  139379  139385  139389  139391  139395  139401  139403  139409  139413  139415  139419  139421  139425  139427  139429  139430  139431  139433  139434  139435  139437  139439  139443  139445  139449  139451  139455  139461  139463  139469  139473  139475  139479  139485  139491  139493  139499  139503  139505  139511  139515  139521  139529  151629 

科目: 来源: 题型:阅读理解

8.Why Blue LED Lights Won the Nobel
The 2014Nobel Prize in physics went to three scientists who gave lighting a big change by inventing blue LED lights.A big change in lighting efficiency is under way around the world.
Save and green
LEDs use less energy than other forms of lighting.A typical LED bulb(灯泡) can produce around 83lumens per watt-a measure of how much brightness you can get from a unit of electrical power-much more efficient than other lighting facilities.
LEDs produce light by passing electric current through a semiconductor,while traditional bulbs pass current through a wire.The wasted heat energy is chiefly why traditional bulbs are so much less efficient.
LEDs also last about 30times longer than traditional bulbs,and many LED bulb products promise up to 25,000hours of use-more than 17years if you used one for about four hours a day.
Lighting the world
The lighting transformation is not only in homes.LEDs are also being used for street lights,public holiday and decorative displays,commercial buildings,and other large energy users.
Car lighting is another application where LEDs are making progress.LEDs used to be used only for daytime running lights,but now many new cars have LED headlights for night-time use.
LEDs also hold promise for bringing light to the more than 1.5billion people around the world without access to electricity,the Royal Swedish Academy of Sciences noted.Indeed,several proposed solutions to energy poverty include the distribution of LED lights,particularly solar-powered ones.
Digital displays
Without blue LEDs,the world wouldn't have back-lit smart phones,TV and computer LCD screens,blu-ray(蓝光) players,many forms of lighting,and countless other products.
In the electronics industry,LEDs provide back lighting for LCD screens in many smart phones,laptops,and televisions.The LEDs are more energy efficient and allow for very thin displays.
Blu-ray players use blue LED lasers(激光) to read data off a digital optical disc.When these systems switched from using an infrared(红外线) laser to a blue LED laser,it became possible to store five to 10times as much data.
LEDs are now being explored for their potential uses to transmit(传送) data from the Internet across open space,similar to WiFi.Such a system could transmit a lot more data than WiFi alone.This high bandwidth is possible because LEDs can turn on and off millions of times per second.
The rise of LED lighting came at a time when people were just starting to be concerned about global warming.Because of LEDs'energy efficiency,using them for the world's lighting would affect environmental protection in a positive way.
Why Blue LED Lights Won the Nobel
The reason why blue LED lights won the 2014 Nobel Prize in physics is that they are to (81)resultin big changes in lighting.
Save and green(82)Comparedwith other forms of lighting,LEDs are much more efficient because of the different ways they pass electric current.
What's more,LED bulbs can be (83)used30 times longer than traditional bulbs.
Lighting the world(84)Apart/Asidefrom household applications of LED bulbs,they can also be used as street lights and car headlights.
Because of their high efficiency,LEDs,especially solar-powered ones,(85)promiseto light areas without access to electricity.
Digital displaysMany smart phones,laptops and televisions use LEDs to back-light their LCD (86)screens.
By using blue LED lasers,blu-ray players are likely to store (87)moredata.
People are now exploring more (88)potentialuses of LEDs such as transmitting data.
(89)ConclusionLED lighting will have a positive (90)impact/influence/effecton environmental protection.

查看答案和解析>>

科目: 来源: 题型:阅读理解

7.When you are in a place where you are hunting for a new job or career,you will find that there are several things that you should pay attention to.Jobs and careers are fewer than you expect,especially when satisfying employment is something you need to seriously think about.How are you going to find the job that you want and what should you avoid(避免) on your way?When you want to make use of your job search,take a moment and think about the things that you must avoid at all costs.
One of the most important rules is never to compromise(妥协) on the things you ask for or desire or it will badly affect your life and peace of mind.Keep in mind your basic expectations of a dream job.They might be something about monetary compensation or you might find they have something to do with time off.Whatever they are,make sure that you do not accept a job without them.Your requirements might not be easy to meet,but you have the right to try and achieve them.
What's more,don't shy away from odd (临时的)jobs that might actually take you to the place that you want to be in.Sometimes,finding the right job is a matter of luck and chance after you have been searching and putting in a lot of effort.And if something unexpected happens,remember that taking the chance is of great importance and is something you might want to seriously consider.As long as you keep your goals in mind,you are going to be doing much better than other people during the job search.
If you are looking for the right job,another thing that you can do to make sure that you get the right kind of employment is to market yourself.When you do nothing to push yourself forward,you will be the one suffering for it.If required,give enough encouragement to yourself and try to confidently look at all that you have.Make sure that you can show your skills and abilities.If the jobs that you have set your sights on are challenging,set goals for yourself and work hard at them.The more efforts you put in marketing yourself,the more your chances of obtaining the job you like will be.
Remember that when you are working on a job search,you should not short-change yourself.This is because you will only harm yourself by setting low goals.

TitleWhat to avoid during your job search
Brief introductionSatisfying jobs are fewer than (71)expected.
When you're hunting for a job,there are some related things that you should take into (72)consideration.
Important
(73)rules
Remembering your expectations.
Don't compromise on your requirements or it will have a(n) bad  (74)effect/influenceon your life.
Although your requirements are (75)hard/difficultto meet,you should try hard.
Taking the chance.
Take some odd jobs and this might help you (76)achieve/reachyour goal finally.
When something unexpected happens,taking the chance is a very (77)importantthing that you should consider seriously.
Marketing yourself.
Positively look at all that you have and (78)encourageyourself.
Show your skills and abilities.
If the job that you want is a(n) (79)challenge,set your goals and work hard.
(80)ConclusionDon't short-change yourself because low goals may harm you.

查看答案和解析>>

科目: 来源: 题型:填空题

6.The boy is such young that he can't go to school.such改为so.

查看答案和解析>>

科目: 来源: 题型:填空题

5.He came late as result of the heavy rain this moring.as后中a.

查看答案和解析>>

科目: 来源: 题型:填空题

4.呼吸.breathe/respire/breath/breathing.

查看答案和解析>>

科目: 来源: 题型:填空题

3.生活方式.lifestyle/lifeway.

查看答案和解析>>

科目: 来源: 题型:书面表达

2.随着因特网的发展,网上购物(Online Shopping)已经成为一种时尚.请根据下表内容,用英语写一篇120词左右的短文,描述网上购物的利与弊,并发表你个人的观点.
                                 网上购物
网购的优点l  提供方便的服务;
l  购买的商品价格低廉;
l  节省时间.
网购的弊端l  商品质量无保证;
l  退还商品不方便;
l  长时间上网对身体有害.
你的观点(至少两点)1….;  2….
注意:开头部分已经给出,不计入总词数.
With the development of technology,online shopping is becoming increasingly popular these days and has become a symbol of fashion.
_________________________________________________________________________________

查看答案和解析>>

科目: 来源: 题型:短文改错

1.每句有一处错误,请按以下要求改错:
错误:把某词改为某词.写为:某词---某词.例如:was--were
增加:在某词后加某词.写为:某词后加某词.例如:by后加the
删除:去掉多余的词.写为:去掉某词.例如:去掉a
71.Comparing with 2005,the price of grain was increased by 50%.
72.Rather than driving himself,he always prefers to ride a bicycle.
73.It will depend on if this problem can be solved.
74.I have some doubt that they can complete the task on time.
75.This teacher often helped me maybe because he felt itself his duty to do so.
76.Some of the tall trees were measured over 90 metres.
77.It's very late to take any buses,so we have to walk home.
78.As long as I know,they live in the same neighbourhood.
79.The organization is in charge of David who is very capable of managing it.
80.We took turn to drive when going to the seaside.

查看答案和解析>>

科目: 来源: 题型:填空题

20.There was a longpausebefore she answered.她停了好一会才回答.

查看答案和解析>>

科目: 来源: 题型:填空题

19.Her time is fullyoccupied(占用) with her three children.occupied.

查看答案和解析>>

同步练习册答案