题目内容

【题目】黄土高原地区开发历史悠久,在全国经济发展中具有重要地位,但近些年来人地矛盾十分尖锐。据此回答下列问题。

1黄土高原最大的环境问题是

A. 荒漠化 B. 水土流失 C. 酸雨 D. 气候变暖

2造成这种环境问题的主要人为原因是

A. 水资源的不合理利用 B. 土壤疏松,降水变率大

C. 过度放牧和过度樵采 D. 干旱和大风现象

【答案】

1B

2C

【解析】试题分析:

1】黄土高原最大的环境问题是水土流失。选B正确。

2】黄土高原长期以来的毁林开荒,是水土流失的主要原因;黄土土持疏松、降水变率大,是水土流失潜在的自然原因;不合理的开垦、开矿、工程建设、破坏植被是水土流失的人为原因;过度放牧和过度樵采及干旱和大风现象是荒漠化的成因。选A正确。

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【题目】 完形填空(共20小题;每小题1.5分,满分30分)

阅读下面短文,从短文后各题所给的四个选项(A、B、C和D)中,选出可以填入空白处的最佳选项。

A learned man always has a lot of riches in himself.

Simonides,a famous Greek poet,once made a tour around the wellknown cities of Asia.Years later,he decided to 1 to his native land by sea.

However,he boarded on a ship,which got 2 in a terrible storm.Together with its own poor condition,the ship began to 3 into the sea.Some passengers was busy 4 together their bags,and their 5 belongings.To everyone’s surprise,Simonides was a(n) 6 .One who was 7 curious,asked,“Are you going to save 8 of your property,Simonides?” He made a reply.“All my possessions are 9 me.”

While a few made their 10 by swimming,the majority,being weighed down by their burdens,disappeared in the sea. 11 ,some thieves made their appearance,and stole 12 the few lucky people had saved,leaving them nothing.

Clazomenae,an ancient city,chanced to be near the beach.Here lived a wealthy man 13 the pursuits(追求) of literature.He had often read the poems of Simonides,and was a very great 14 of him though he had never seen Simonides. 15 ,Simonides was saved by this man shortly after he got to the beach.Knowing who he was from their brief conversation,the man 16 Simonides into his house with the greatest pleasure,and 17 him with clothes,money,and attendants.The other 18 meanwhile were carrying about their bowls,begging for food in the same city.One day,Simonides 19 to meet them.With much sympathy,Simonides remarked,“I told you that all my property was about me;what you have 20 to save is lost now.”

【1】A. return B. get C. visit D. come

【2】A. hit B. caught C. struck D. seized

【3】A. break B. drown C. fall D. sink

【4】A. gathering B. keeping C. joining D. carrying

【5】A. common B. formal C. precious D. previous

【6】A. millionaire B. example C. fool D. exception

【7】A. slightly B. extremely C. gradually D. generally

【8】A. nothing B. few C. none D. no one

【9】A. about B. around C. of D. for

【10】A. effort B. effect C. escape D. attempt

【11】A. In fact B. In brief C. After all D. Worse still

【12】A. that B. what C. which D. when

【13】A. related to B. adapted to C. determined to D. devoted to

【14】A. adviser B. listener C. admirer D. buyer

【15】A.Unluckily B. Fortunately C. Naturally D. Frequently

【16】A. ordered B. forced C. received D. begged

【17】A. provided B. offered C. showed D. afforded

【18】A. villagers B. writers C. stealers D. survivors

【19】A. hoped B. happened C. managed D. demanded

【20】A. struggled B. failed C. encouraged D. succeeded

【题目】A

It might seem hard to imagine that a bad tooth could be deadly.But doctors in the Washington area say a twelveyearold boy died last month of a tooth infection that spread to his brain.They say it might have been prevented if the boy had received the dental care he needed.

Experts at the National Institutes of Health say good dental care should start at birth.They say breast milk is the best food for the healthy development of teeth.Breast milk can help slow bacterial growth and acid production in the mouth.

When baby’s teeth begin to appear,you can clean them with a wet toothbrush.Dentists say it is important to find soft toothbrushes made especially for babies,and use them very gently.

The use of fluoride (氟化物) to protect teeth is common in many parts of the world.This natural element is often added to drinking water supplies.The fluoride mixes with enamel(釉质),the hard surface on teeth,to help prevent holes,or cavities from forming.

But the American Academy of Pediatric Dentistry points out that young children often swallow toothpaste when they brush their teeth.The group notes that swallowing fluoridated toothpaste can cause problems.So young children should be carefully supervised when they brush their teeth.And only a small amount of fluoridated toothpaste,the size of a green pea,should be used.

Parents often wonder what effects sucking a thumb or sucking on a pacifier might have on their baby’s teeth.Dental experts generally agree that this is fine early in life.

The American Academy of Family Physicians says most kids stop suckingtheir thumbs by the age of four.If it continues,the group advises parents to talk to their child’s dentist or doctor.It could influence the correct development of permanent teeth.

【1】The boy with a bad tooth died because ________.

A.his tooth disease was very deadly

B.the doctor refused to treat him properly

C.he didn’t receive timely treatment

D.something was wrong with his brain

【2】All the following statements are good to teeth except that ________.

A.children live on breast milk every day

B.children begin to brush their teeth when they are old enough

C.children use fluoride toothpaste to brush their teeth

D.children form the habit of sucking their thumbs

【3】The underlined word “supervised” in the fifth paragraph means “________”.

A.watched and directed B.taught and helped

C.praised and advised D.led and pointed out

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