Gray hair is simply a part of the normal aging process, and the rate you go silver is genetically predetermined. Going gray is not associated with earlier death, and premature graying is not, generally speaking, a sign of an illness or ill health in younger adults. There are, however, some specific health conditions associated with gray or white hair, but for most of us, going gray is just a fact of life.
Hair color comes from the pigment melanin(黑色素), which determines your individual shade. Hair without any melanin is pure white. The pigment is produced in cells called melanocytes, which inject pigment into the hair. At some point in everyone's lifetime, these cells slow down and eventually stop producing color. Scientists have yet to identify the exact mechanism by which melanocyte cell death occurs.
A study of more than 4,000 women and men from 20 countries determined that about 75% of people between the ages of 45 and 65 have some gray hair. In general, people of European descent gray earliest followed by Asians and Africans. It's interesting to note that a lucky 1 in 10 has no gray hair by retirement age. Beginning at age 30, your chances of having gray hair go up 10-20% per decade.
It may feel like you have more grays after a stressful event, but that's probably because middle age is basically a series of anxiety-ridden events. Between working, raising kids, and caring for older parents, the "sandwich" years of 45-65 can be stressful, especially for women. They are also when we naturally start to look older.
At this point, there is still no silver bullet to keep away the grays.
【小題1】What would be the best title for this passage?

A．Going gray. B．Tips to make hair color last
C．Why does hair turn gray? D．Gray hair is in fashion.
【小題2】Which of the following is a true statement according to the passage?
A．Scientists have found out how to prevent hair from turning gray.
B．Europeans are more likely to gray than Asians and Africans.
C．Gray hair means poor health or a sign of illness.
D．Everyone will inevitably get gray hair by retirement age.
【小題3】Which is not among the reasons for hair turning gray according to the passage?
A．Being physically weak. B．Stress from different sides.
C．Death of melanocyte cell. D．Genetic factors.
【小題4】What does “silver bullet” in the last paragraph probably mean?
A．Make-up B．Scientific research. C．Chemical weapon. D．Cure.


【小題1】C
【小題2】B
【小題3】A
【小題4】D

解析試題分析：本文介紹了為什么人的頭發(fā)會(huì)變白。這是自然老化的過程、與基因有關(guān)，還和黑色素的分泌的多少有關(guān)，黑色素越少，頭發(fā)越白。通過研究20多個(gè)國(guó)家的4000多男性和女性可知，有年齡原因也有地域原因。生活壓力大也是原因之一。
【小題1】主題歸納題。根據(jù)全文尤其是文章的第一句話判斷，文章是在講頭發(fā)變白的應(yīng)用。所以選C。
【小題2】推理判斷題。根據(jù)第三段的In general, people of European descent gray earliest followed by Asians and Africans.可知：歐洲人早于亞洲人和非洲人頭發(fā)變花白。B
【小題3】細(xì)節(jié)理解題。根據(jù)第一段的內(nèi)容可知，銀發(fā)是一個(gè)正常老化的過程，頭發(fā)變白由基因已經(jīng)決定了的。與早亡無關(guān)，少白頭也不是生病或者身體不舒服的標(biāo)志。所以選A（身體虛弱）。
【小題4】詞義推測(cè)題。根據(jù)最后一段的意思可知：人在45-65之間壓力很大，尤其是婦女，還有自然的老化問題。所以選D（治愈）。其他選項(xiàng)的意思是：Make-up化妝；Scientific research.科學(xué)研究；Chemical weapon.化學(xué)武器。
考點(diǎn)：科普類閱讀。

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Of all the animals in the animal kingdom, which one (aside from man) is the cleverest?
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【小題1】Which is the best title?

A．The Elephant’s Memory B．The Cleverest Animal
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B．When people get older, they have no young children to care about. 
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A．Advice to the young people on how to keep happy. 
B．Why women at all ages are more sad, stressed and worried. 
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D．Why people will grow happier with their ages. 
【小題5】 What do you think the Proceedings of the National Academy of Sciences is?
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A．One's heart affects how he feels fear.
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D．One’s fast heartbeats are likely to cause fear.
【小題2】The study was carried out by analyzing _______.
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【小題1】The first regularly printed European newspaper started in ________.

A．Rome in 59 BC B．Germany in 1609 
C．Amsterdam in 1620 D．England in 1621 
【小題2】The first daily newspaper in English started in _________.
A．1620 B．1621 C．1590 D．1702 
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A．History of newspapers 
B．History of daily newspapers 
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Below is a discussion on a website.

http://www.TalkingPoints.com/
Stuck on a desert island?
Started on 23rd April by Steve Posts 1 – 7 of 42
Post 1
Steve
USA
Hi, everyone. What would you miss most and least if you were stuck on a desert island? For me, it would be the changing seasons in New England. I guess this will sound stupid but I’d probably miss the rain, too. I wouldn’t miss getting up at six every day to go to work, though! What about you?
Post 2
Tomas
Germany
Good question. Steve, I think I’d miss different types of bread, and shopping at the supermarket. I’d miss the food most. What would I miss least? My mobile phone---I’d like to be completely quiet --- at least for a little while
Post 3
Paola
Italy
I would miss the company of people because I know I’d like to have someone to share experiences with. I’d go mad on my own. And I sure wouldn’t miss junk mail(垃圾郵件) --- I hate coming home every evening and a pile of junk mail in my post box.
Post 4
Miko
Japan
Hi, I would miss Manga cartoon, the Internet and Japanese food, like sushi. I’d also miss TV shows and shopping for clothes…
Post 5
Roger
UK
I would miss my daily newspaper and listening to the news on TV and radio. I’d feel very cut off if I didn’t know what was happening in the world. What I’d miss least would be traffic jams in the city, particularly my journey to work.
Past 6
Jayne
Why hasn’t anyone mentioned their family? I’d be lost without my husband and two kids. They’re the most important for me. And I can’t get started in the morning without a cup of black coffee. I wouldn’t miss doing the housework!
Post 7
Jaime
Mexico
It would have to be music. I couldn’t live without my music. I wouldn’t miss going to school at all or doing homework!
【小題1】 Who would miss his or her family most?
A．Jaime B．Jayne C．Miko D．Paola.
【小題2】Which of the following people would feel most uncomfortable without the news media?
A．Steve. B．Jaime C．Roger. D．Tomas
【小題3】How many of them mentioned that they would miss food or drink?
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Can we give a hand to those endangered animals? Yes, we may only do a little bit, but together our small actions add up to a lot.
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2. Reduce the threat of invasive (入侵的) species.
The spread of non-native species has greatly reduced native populations around the world. Invasive species compete with native species for resources (資源) and habitat. They can even prey on native species directly, forcing native species towards extinction.
3. Place decals (貼花紙) on windows.
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4. Slow down when driving.
Many native animals have to live in developed areas and this means they must move in human-living areas. One of the biggest obstacles (障礙) to them is that created by roads. Roads divide habitat and present a constant risk to any animal attempting to cross from one side to the other. So when you’re out and about, slow down and keep an eye out for wildlife.
【小題1】 What would be the best title for this passage?

A．How animals go to extinction
B．The importance of protecting wildlife
C．What to do to help save wildlife
D．How to protect wildlife habitat
【小題2】By writing the underlined sentence, the writer means that _____.
A．more parks and reserves should be built
B．we should have more habitats free of destruction
C．there is a need for improvement in parks and re-serves
D．parks and reserves are good examples of protecting wildlife
【小題3】People are advised to put decals on windows to _____.
A．decorate the houses and beautify the environment
B．protect the windows from birds hitting
C．a(chǎn)ttract more birds to make homes nearby
D．a(chǎn)void birds hitting the windows by mistake
【小題4】The underlined phrase “prey on” in the passage means _____.
A．drive awayB．live withC．kill for foodD．fight with

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科目：高中英語 來源： 題型：閱讀理解

Hospital emergency rooms treat injured fingers all the time. Without treatment, a bad cut can lead to permanent damage. But how should a person know when a bleeding cut is serious enough to require medical attention? We asked Dr Martin Brown, chairman of the department of emergency medicine at Inova Alexandria Hospital in Virginia.
First, the medical term for a cut or tear in the skin is a laceration(嚴(yán)重劃破，撕裂傷). Dr Brown says the length is usually not as important as the depth. He says a long cut on a finger can likely be treated without a visit to a doctor if the wound is not very deep. “If you have a short but deep laceration where there’s been a structure underneath that’s been damaged － a tendon, a nerve, a blood vessel,” says Martin, “it may, in fact, need professional attention.”
Some injuries － like a fingertip that gets cut off － might even require surgery to repair. That requires a specialist to either file(銼平) down the bone or reattach the fingertip. More often, filing down the bone is what is done because reattaching a fingertip is often not successful.
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Even a cut that does not require medical attention must be kept clean to prevent infection. Small cuts should be cleaned gently with clean water. Use a washcloth to clean the area if the wound is dirty. Dr Brown says cuts should be covered with a clean, dry bandage.
【小題1】What does the writer want to tell the readers in the first paragraph?

A．Hospital emergency rooms always treat injured fingers. 
B．A bleeding cut is serious enough to require medical attention 
C．Dr Martin Brown is in charge of Inova Alexandria Hospital. 
D．It is important for us to be able to tell how serious a finger cut is. 
【小題2】According to the passage,         .
A．a(chǎn) finger cut without treatment can lead to permanent damage 
B．the length of a cut on a finger is more important than the depth 
C．a(chǎn) long but not very deep cut often doesn’t need professional attention 
D．a(chǎn) short but deep laceration that has been damaged need professional attention. 
【小題3】The underlined word “reattach” in Para.3 is closest in meaning to         .
A．repair B．rebuild C．reconstruct D．reconnect 
【小題4】Which of the following statements is NOT true according to the passage?
A .How a wound bleeds can show us how serious the wound could be.
B Venous bleeding will often stop when we put pressure on the wound.
C. Holding up the hand with a finger cut can reduce the loss of blood.
D. Arterial bleeding should get professional treatment as soon as possible
【小題5】.The best title of this passage should be         .
A．Hospital Emergency Treatments For Injured Fingers 
B．When a Cut Finger Is More Serious Than It Might Seem 
C．Serious Finger Cut That Requires Medical Attention 
D．Keep Finger Cuts Clean to Prevent Serious Infection 

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