A pulse is applied to each input of a 2-input NAND gate. One pulse goes HIGH at t=0 and go

A、It goes LOW at t=0 and back HIGH at t=3ms. 该脉冲在t=0ms降为低电平，t=3ms时返回高电平。

B、It goes LOW at t=0.8ms and back HIGH at t=3ms. 该脉冲在t=0.8ms降为低电平，t=3ms时返回高电平。

C、It goes LOW at t=0.8ms and back HIGH at t=1ms. 该脉冲在t=0.8ms降为低电平，t=1ms时返回高电平。

D、It goes HIGH at t=0.8ms and back LOW at t=1ms. 该脉冲在t=0.8ms升为高电平，t=1ms时返回低电平。

What is Nancy most likely to do in Cambridge?

A．She goes there to further her studies.

B．She goes there to do some business.

C．She goes there to conduct a project.

D．She goes there to apply for a teaching job.

Passage 4

It’s a good idea to apply sunscreen before heading to the beach if you don’t want to bum. But for marine animals like whales，they don’t have that _1_. Species like sperm whales can spend up to six hours at the ocean’s surface in between dives, _2_ in the sunlight. So how do they protect themselves from a serious case of sunburn? It turns out that their bodies have a similar defense _3_ against the sun’s UV radiation as people. Blue whales—which have the lightest skin color of the three species—tan during their summer stay before _4_ back to their northern feeding grounds. Sperm whales don’t tan. They can receive an “overdose” of UV radiation during their hours at the ocean’s surface, and they have proteins that _5_ protect their cells from UV damage. This process is _6_ to how human bodies produce antioxidants in response to molecules that can cause a lot of genetic and cellular damage. And fin whales escape sun damage thanks to their high levels of melanin—a dark substance in the skin to protect humans from UV radiation. Older whales and whales with less _7_ of melanin in their skin—like blue whales—had the greatest level of damage in their mtDNA. Fin whales, which had the greatest amount of melanin, had the least amount of mtDNA damage. Now that the ozone layer that shields Earth from UV radiation is gradually _8_, it’s important to know what the consequences are for whales and dolphins, especially for _9_ or endangered species. Although it’s difficult to tell what causes many of these skin conditions, UV damage is one cause. Even though whales have _10_ defenses to UV radiation, high exposure can still be harmful.

A) similar

B) diminishing

C) liability

D) migrating

E) mutual

F) mechanism

G) effectively

H) jerking

I) instantaneously

J) vulnerable

K) content

L) baking

M) inherent

N) perspective

O) option

第1空答案是：

The article consists of three stories about pioneersof fight The first story is about a Chinese named Wan Hu, who made an unsuccessful attermpt at .1in AD.1500 He buit a spaceship powered by 47rockets using. 2 His idea was crazy, but his dreamof fight, 3 500 years later when China successfully launched its first manned Shenzhou V spaceship.The second one is about the Spruce Goose, a_ 4designed to meet the need of 5 troops andmaterials during World War I. It was made entirely of6 and still holds the recordfor，Z Althoughit wasnever put to use, many of its design features have been incorporated into today's 8 The last is about Leonardo da Vincl, the most famous artist of the Renaissance. Apart from his great artistic work, he also drew sketches of.9 with flapping wingscorntrlled and steered by .10 Five hundred years later, a professional parachutist made a successful jump using a wood and canvas parachute based on one of da Vincil 's desins/sketches.

A.human pilots; B.the greatest wingspan; C.cametrue; D.spaceflight;

E.wood; F.flying devices;G gunpowder; H.cargo planes;I.transporting; J.flying boat

Once a chief (酋长）told a servant(仆人）to go to the market. "Bring me the best piece of meat that is sold in the___26___ .’’said the chief.

The servant ___27___ at once and ran to the market. The chief was surprised when the servant came ___28___ with thetongue of a cow.

It didn’t seem to be good to ___29___? Yet when it was prepared by the ___30___, the chief was satisfied. The meat was truly ___31___? It was quite pleasing to eat. The chief called the servant to him again. &39;

The tongue was ___32___ wonderful. Now go to the market again and___33___ me the worst piece of meat that is sold there.” The servant obeyed once again. He ran ___34___ to the market. Soon he came back ___35___ a piece of meat thatlooked like the first. The chief was astonished that the servant once again brought him a tongue from another ___36___?

“What is this?” asked the chief, “When I asked you to fetch me the best piece of meat, you brought me the tongue. When I asked for the worst one, you brought me another tongue. Are you ___37___ me? ”

The servant answered, “The tongue can be ___38___ or ugly, It can be sweet or bitter. It ___39___ the words and soundsthat arc heard by the ___40___? If a person words are kind and sweet, the tongue is at its best. It is delicious to the car. The___41___ of the tongue bring happiness. If the words we say are rude and sharp, they can be hurtful and ___42___. They canbring sadness and ___43___

“Thank you,” said the chief. “Your words are wise,” Then he said to his people, “May the words of all of us be ___44___and delicious to all who ___45___ them.”

26__________

A.country

B.village

C.market

D.city

27A.replied

B.cried

C.escaped

D.obeyed

28A.out

B.back

C.down

D.along

29A.eat

B.sell

C.smell

D.touch

30A.villagers

B.women

C.children

D.cooks

31A.clean

B.delicious

C.big

D.strange

32A.really

B.merely

C.usually

D.slightly

33A.lend

B.tell

C.offer

D.bring

34A.suddenly

B.sadly

C.quickly

D.regularly

35A.carrying

B.cutting

C.eating

D.pulling

36A.sheep

B.horse

C.duck

D.cow

37A.teaching

B.pleasing

C.fooling

D.helping

38A.beautiful

B.useful

C.expensive

D.interesting

39A.asks for

B.lives on

C.depends on

D.looks for

40A.chief

B.listener

C.servant

D.seller

41A.sounds

B.colors

C.roots

D.shapes

42A.difficult

B.meaningful

C.bitter

D.true

43A.pity

B.pain

C.wonder

D.effect

44A.special

B.right

C.funny

D.sweet

45A.read

B.hear

C.speak

D.write

请帮忙给出每个问题的正确答案和分析，谢谢！

The following is a list of sentences which forms an introduction section. Read each of them and rearrange them in a logical order of the introduction. a. With the application of audio and visual materials in teaching, the class will become alive and attractive. b. and then analyze the advantages they will bring to the teachers as well as students. c. Teaching method is always a heated topic for teachers to make his or her class well. d. Such a class can not only develop students’ initiatives but also improve teachers teaching performance. e. Multimedia techniques will help teachers make a class better. f. The essay will first demonstrate the significance of multimedia techniques; g. Traditional classes are teacher-centered and the teaching pattern is “one chalk, one blackboard”. h. According to Wikipedia, multimedia techniques refer to the techniques of the combined use of media such as television, slides, etc, esp. in education. i. The purpose of the essay is to study the advantages multimedia techniques bring to a class. j. This pattern can easily lead to a boring and tedious class.

听力原文： Let children learn to evaluate their own work. A child learning to talk does not learn by being corrected all the time. He notices a thousand times a day the difference between the language he uses and the language those around him use. Bit by bit, he makes the necessary changes to make his language like other people's. In the same way, when children learn to do all the other things, for example, to walk, run, climb, ride a bicycle, they learn to do them without being told. They compare their performances with those of more skilled people, and slowly make the needed changes. But in school we never give a child a chance to find out his own mistakes for himself, let alone correct them. We do it all for him as If we thought that he would never notice a mistake unless it was pointed out to him, or correct it unless he was made to. Soon he became dependent on the teacher. Let him do it himself. Let him work out, with the help of other children, what this word means, what answer is to that problem, whether it is a good way to say or do this or not.

If it is a matter of right answers, give him the answer book. Let him correct his own papers. Why should we teachers waste time on such routine work? Our job should be to help the child when he tells us that he can't find the way to get the right answer. Let's end this nonsense of grades, exams, marks. Let's throw them all out, and let the children learn what all educated persons must some day learn, how to measure their own understanding, how to know what they know or do not know.

(23)

A．They learn to do them by being corrected all the time.

B．They learn to do them by being taught by skilled people.

C．They learn to do them through comparison and discovery.

D．They learn to do them with the help of other children.

Of all things in the world, I most dislike filling up forms. In fact, I have a positive horror of it. Applying for a driving licence, registering for an evening course, booking a holiday abroad--every thing nowadays seems to involve giving information about one' s personal life and habits that has little or nothing to do with the matter in hand. When applying for a job, it may be of some obscure interest to a prospective employer to learn that I collect stamps or had measles as a child, but why should he want to know that my father was a tobacconist who lived in Fulham and died when he was 82?

The authorities who require one to fill up forms frequently demand answers to questions that one would hesitate to put to one's intimate friends. The worst of it is that, when faced with such questions, my mind goes blank and I can hardly remember my own date of birth, let alone my nationality. Have I ever suffered from a serious illness? Have I7 What do they mean by ' serious' 7 I had my tonsils out in hospital when I was eight, and my mother always assured me I was ' delicate' , but father contended I was born lazy. Do I suffer from any personal defects? Well, I wear contact lenses and my upper teeth are not my own, but perhaps the word ' defects' applies to my character. Am I supposed to admit that I like gambling, and find it difficult to get up in the morning? Both of which are true.

Of all, I think job applications are the worst. ' Education--previous experience--posts held-- give dates... ' Terrified by the awful warning about giving false declarations which appears at the bottom of the form, I struggle to remember what exams I passed and how long I worked for what firms. However hard I try, there always seems to be a year or two for which I cannot satisfactorily ac count and which I am certain, if left blank, will give the impression that I was in prison or engaged in some occupation too dubious to mention. Even when the form. is safely posted, there is no relief as I hourly await and order from angry official to explain differences on my form.

In the opinion of the writer most forms require one to supply ______.

A．irrelevant details

B．positive answers

C．secret information

D．personal problems