如图是日光灯的电路图.日光灯主要由灯管、镇流器、启动器组成.关于日光灯的原理，下列说法正确的是( )
| A．日光灯启动，利用了镇流器中线圈的自感现象 |
| B．日光灯正常发光时，镇流器起着降压限流的作用 |
| C．日光灯正常发光后取下启动器，日光灯仍能正常工作 |
| D．日光灯正常发光后取下启动器，日光灯不能正常工作 |
【原创】People feel ______(puzzle) by some unexplained phenomena, one example of
is the possible existence of Yeti.
is said that the Yeti is__
___(tall) than an average human but walks with amazing speed and strengths. Though some people even reported____
____(see) the footprints belonging to a Yeti, no stronger evidence for its ____
___(exist) has been found.
_____the development of science and technology, __
_____ is unknown to us today ___
___(be) explained in the future. We hope that __
____(science) will solve the mystery one day and give us a satisfactory answer.
【原创】Three years ago I______（fail）an important exam in my life and became__
___ student in an ordinary school.____
____（disappoint）as I felt at the shabby campus and the poorly-equipped classroom, I found the teachers patient and____
______ （consider）. Besides, I enjoyed the ____
___(friend) atmosphere in class. I decided to make the best of it. I worked hard and get along well ___
___ my teachers and classmates.
________ I had difficulties, they were always available. Soon, I became one of the top students in my class,___
__ greatly increased my___
______ (confident) and got me motivated.
My experience tells me that it is not what you are given but how you make use of it ___ determines who you are.
The way we cook is important. In many countries, the two choices are (nature) gas or electric-powered stoves.
The World Health Organization warns that millions of people (suffer) from indoor air pollution at present time, which results from the use of
(danger) fuels and cook-stoves in the home.
WHO officials say nearly three billion people are (able) to use clean fuels and technologies for cooking ，heating and lighting. As a result, more than seven million people die from exposure to indoor or outdoor air pollution each year. Most of the deaths are in
（develop） countries, such as lndia, China and Latin American countries.
WHO officials say opening a window or door （let）out the harmful air will not correct the situation
will only pollute the outdoors.
Nigel Bruce, is a professor of Public Health at the University of Liverpool, says researchers are developing good cook-stoves and other equipment to burn fuels
a more efficient way.
But, this is just a start. It is urging developing countries to use (clean) fuels and increase access to cleaner and more modern cooking and heating appliances（用具）.
Eleven-year-old Angela was stricken with a disease involving her nervous system．The doctors did not hold out much hope of her ever recovering ____ this illness．They predicted she’d spend the rest of her life in a wheelchair．
_ Angela firmly believed that she was definitely going to be walking again someday．The doctors were charmed by her __
__（defeatable）spirit．They taught her about imaging—about seeing herself _
（walk）．Angela would work as hard as possible in physical therapy(理疗），lying there faithfully doing her imaging，visualizing herself moving，moving，moving!
One day，____ she was straining with all her might to imagine her legs moving again，__
_ seemed as though a miracle happened: the bed moved! She screamed out，“Look what I __
_（do）! Look! Look! I can do it! I moved，I moved！” Of course，__
__ this very moment everyone __
__ in the hospital was screaming，too．It was the San Francisco earthquake．But don’t tell _
__ to Angela．She’s convinced that she did it．And now only a few years later，she’s back in school．On her own two legs．No walking sticks，no wheelchair．
Recently a new science behind incentives(激励), _(include) in education, has been discussed. For example, researcher Roland Fryer wanted to see what works best in motivating children
___(do) better in school. _
__some cases, he gave students incentives based on input(输入), like reading certain books, while in _
__, the incentives
_(base) on output, like results on exams. His main
__ (find) was that incentives increased achievement when based on input but had no effect when based on output. Fryer’s conclusion was that the incentives for inputs might be
_____ (effect) because students do not know how to do better on an exam, apart from general rules like “study harder”. Reading certain books, on the other hand, is a well-set task over
____they have much more control.
As long as you have direct control over your goal, you have ___ much higher chance of success. And it’s easier to start again
_you fail, because you know exactly what you need to do.
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