7．Have you ever wondered why there are so many skin colours in the world？Do you know why people living in particular areas usually have a certain colour？Biology and history are the two reasons for this．
Skin contains something called melanin，which determines a person's skin colour．The more melanin a person has，the darker his or her skin will be．The amount of and production of melanin are controlled by genes，but can be affected by other things，such as sunlight．If a person lives in a place with strong sunlight，his or her skin will protect itself by producing more melanin，making the skin darker．In a place with less sunlight，a person's body will produce less melanin，making the skin lighter．
Skin colour is also affected by another source-vitamin D．Humans all need vitamin D to build bones．People can get it by eating foods such as fish and milk，or from sunlight，which causes vitamin production in the skin．Melanin protects skin by absorbing sunlight，so sunlight absorbed by melanin cannot be used for vitamin D production．Therefore，a dark-skinned person will produce less vitamin D than a light-skinned person when they receive the same amount of sunlight．
The connection between vitamin D production and skin colour is clear when we look at evolution．The earliest humans lived in Africa，their dark skin covered with hair．When they moved to places that had less sunlight，their bodies produced less vitamin D because of their dark skin．As a result，their skin made less melanin，so they could get enough sunlight to produce vitamin D．Their skin gradually got lighter and they lost hair．Now，people who live in areas with strong sunlight，like Africa，have darker skin，while people living in other areas have lighter skin．The exception to this is the Inuit，who live in a place with little sunlight，but have dark skin because they eat a lot of fish and have enough vitamin D．
Evolution has given us a rainbow of skin colours．Humans have always had melanin to determine our skin colour．What has changed through history is the environment where we have lived．This has in turn changed our melanin production，and eventually，skin colour．
A World of Skin Colour
Brief introductionPeople living in a particular area usually have the   （71）sameskin colour and there are many different skin colours in the world．
Reasons for skin colourThe reasons for different skin colours mainly （72）lie/consist  in biology and history．
Biological reasonsThe amount of melanin，by which a person's skin colour is （73）determined，varies from people to people．The more melanin a person has，the （74）darkerhis or her skin will be．
Vitamin D is another source （75）affectingskin colour．Vitamin D is necessary for humans to build bones．Sunlight contributes to vitamin D production in the skin．
（76）Historical
reasons		The earliest people in Africa had dark skin with hair covering it because the sunlight is very strong．．
When they moved to places where they could not get enough sunlight to （77）producevitamin D，their skin colour became lighter．
Generally speaking，people in areas with strong sunlight，have darker skin （78）whilepeople in other areas have lighter skin．
（79）Conclusion/SummaryMelanin （80）playsan important role in our skin colour．With our living environment changing，melanin production is changed，which leads to the changes in our skin colour．

分析 為什么不同的人會又不一樣的皮膚？從歷史和生物角度分析了原因．

解答 71．same  72．lie/consist   73．determined  74．darker   75．a(chǎn)ffecting76．Historical  77．produce  78．while  79．Conclusion/Summary  80．plays
71．same 歸納總結(jié)題．根據(jù)文章第一段內(nèi)容可知．Do you know why people living in particular areas usually have a certain colour？住在同一個(gè)地方的人有同樣的皮膚．
72．lie/consist   原詞再現(xiàn)．根據(jù)第一段最后一句Biology and history are the two reasons for this．說明膚色不同是因?yàn)樯飳W(xué)和遺傳，故轉(zhuǎn)換成原因在于lie in
73．determined句意轉(zhuǎn)換．根據(jù)第二段第一行which determines a person's skin color，把這個(gè)主動(dòng)句變成了被動(dòng)形式．
74．darker 句型轉(zhuǎn)換．根據(jù)第二段1，2行The more melanin a person has，the darker his or her skin will be．一個(gè)人黑色素越多，一個(gè)人的皮膚就越黑，一個(gè)句型，the 比較級…the比較級…
75．a(chǎn)ffecting原詞再現(xiàn)．根據(jù)第三段第一句Skin color is also affected by another source----vitamin D．轉(zhuǎn)換成現(xiàn)在分詞短語修飾another source．
76．Historical 詞形轉(zhuǎn)換．根據(jù)第三段內(nèi)容介紹，Biology and history are the two reasons for this．是從歷史方面解釋原因．
77．produce原詞再現(xiàn)．根據(jù)第四段第四行they could get enough sunlight to produce vitamin D．their skin gradually got lighter and they lost hair．
78．while  原詞再現(xiàn)．根據(jù)第四段Now，people living in areas with strong sunlight like Africa，have darker skin，while people living in other areas have lighter skin．生活在陽光強(qiáng)烈的地區(qū)如非洲，皮膚越黑，然而其他地區(qū)的人皮膚呈現(xiàn)淺色．while此處前后兩者情況對比．
79．Conclusion/Summary  歸納總結(jié)．通讀全文可知這里是得出的最終的結(jié)論．Conclusions就是上文得到的最后的結(jié)論．
80．plays固定詞組．Play a role in…在…中起作用．Play a part/role in…主語是不可數(shù)名詞Melanin，故用單數(shù)形式．

點(diǎn)評 對于抽取重要信息題，一定 要注意首字母的大小寫問題．作為題目的單詞的首字母都要大寫；其他句子的第一個(gè)單詞首字母要大寫．

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科目：高中英語 來源： 題型：填空題

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▲Talk to the happiest and most successful people you know．（38）D
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科目：高中英語 來源： 題型：填空題

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All this will help your little one develop a healthy eating habit．And always remember love and care is the key to help you child out of trouble and grow up happily．

Title：（71）Emotional Eating in Young Children
（72）Meaning/DefinitionEating for feeling good instead of for （73）hunger/being hungry/feeling hungry．

Causes		•forming the habit when （74）young/they are young
•feeling  （75）unhappy and bored
•feeling （76）less popular/unpopular and getting low grades
•being made fun of by others



（77）Solutions/Measures/Suggestions		•staying with your child for some time every day
•being （78）interested  in your child's studies and help him study
•providing a healthy environment without tension at home
•avoiding（79）scolding your child to make him ashamed
•making your child（80）confident/have/develop confidence/believe  in himself
•giving your child enough to eat once in a while
•giving your child reward for what he has achieved
ConclusionLove and care helps children out of trouble．

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科目：高中英語 來源： 題型：完形填空

16．Fifteen percent of US teenagers aged 12 to 17 who own mobile phones have received nude（裸體）or nearly nude images of someone they know，according to a survey released on Tuesday．
Only four percent of mobile phone-owning（35）Ain that age group have sent sexually suggestive pictures of themselves，a practice known as"sexting，"（36）Dthe Pew Research Center's Internet & American Life Project．
The Pew survey found that girls and boys were equally as likely to have sent a suggestive picture to（37）Bperson and（38）Cteenagers were more likely to have engaged in"sexting．"
Eight percent of 17-year-olds with mobile phones have sent a sexually provocative（刺激的） image（39）Atexting and 30 percent have（40）Ba nude or nearly nude image on their phone．
Only four percent of 12-year-olds have sent suggestive images of（41）B．
Amanda Lenhart，a senior research specialist at Pew and the author of the report，said sexually suggestive images have become a（42）Dof"relationship currency"for teens．
"These images are（43）Aas a part of or instead of sexual activity，or as a way of starting or（44）Ca relationship with a significant other，"she said．"And they are also passed（45）Ato friends for their entertainment value，as a joke or for（46）B．"
"The desire for risk-taking and sexual exploration during the teenage years（47）Cwith a constant connection via mobile devices creates a'perfect storm'for sexting，"said Lenhart．
"Teenagers have always grappled with issues around sex and（48）D，but their coming-of-age mistakes transgressions have never been so easily（49）Aand stored for others to see，"she added．
The survey found that teens with unlimited text messaging plans were more likely to receive"sexts"（50）Aimages of people they know．About 75 percent of mobile phone owning teens have unlimited plans．
Among this group，Pew said 18 percent reporting receiving"sexts"（51）Bwith eight percent of teens on（52）Adata plans and three percent of teens who pay per message．
According to Pew，58 percent of 12-year-olds own a mobile phone and 83 percent teens aged 17（53）C．
Pew noted that a number of US states are grappling with how to（54）B"sexting"among minors and some legislatures（立法機(jī)關(guān)） have stepped in to consider laws that would downgrade charges from felonies（重罪） to misdemeanors（輕罪）．
Pew conducted telephone interviews with 800 teens aged 12 to 17 and their parents between June 26 and September 24．

35．A．teensB．a(chǎn)dultsC．studentsD．parents
36．A．referring toB．reportingC．sayingD．a(chǎn)ccording to
37．A．otherB．a(chǎn)notherC．othersD．the other
38．A．youngerB．fewerC．olderD．more
39．A．byB．inC．onD．through
40．A．a(chǎn)cceptedB．receivedC．sentD．mailed
41．A．othersB．themselvesC．himselfD．herself
42．A．habitB．systemC．methodD．form
43．A．sharedB．limitedC．tastedD．controlled
44．A．remainingB．gainingC．maintainingD．obtain
45．A．a(chǎn)longB．byC．a(chǎn)sD．for
46．A．joyB．funC．excitementD．delight
47．A．comparedB．followedC．combinedD．went
48．A．friendshipsB．scholarshipsC．relativesD．relationships
49．A．transmittedB．transformedC．formedD．switched
50．A．containingB．concludingC．includingD．concerning
51．A．comparingB．comparedC．connectedD．joined
52．A．limitedB．unlimitedC．fewD．little
53．A．haveB．sameC．doD．too
54．A．do withB．deal withC．removeD．ban

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科目：高中英語 來源： 題型：選擇題

17．Don't feel guilty about it．Anyone _________make mistakes in their life．（　�。�
A．canB．mustC．shallD．need

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