题目内容
6．Use your head．Nothing taught by others can have the same effect on you as ______learned by yourself．（ ）| A． | those | B． | what | C． | that | D． | the one |
分析 用你头脑去思考，别人教的东西没有你自己通过练习学会知识有一样的效果．
解答 答案是C．考查代词辨析．That指代可数名词单数或者不可数名词，后面必须要有定语修饰．what是疑问代词，表示什么．The one指代可数名词单数，表示特指那一个．Those指代可数名词复数，后面必须有定语修饰．句意：用你头脑去思考，别人教的东西没有你自己通过练习学会知识有一样的效果．句中的that指代something，后面有定语learned through practice修饰．故选C．
点评 解答此类问题首先需要理解每个单词的基本含义，然后结合语境选择正确答案．
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17．It's easy to see how the sawfish got its name．These frightful creatures can grow to be more than 6 meters long．Their bodies are flat and winged，like underwater airplanes．And their noses are shaped like chainsaws．
Sawfish are food hunters of the sea．When a sawfish is hungry，it waves its sharp-toothed snout （口鼻部） through a group of fish．Then，it lifts its nose and uses its mouth to draw the injured victims．
Hardy （适应力强的） population of sawfish thrived in warm waters along coastlines around the world for thousands of years．Over the past 200 years，however，human actions have severely endangered sawfish．Threats include fishing nets that trap the huge animals，often by mistake．
Some people collect sawfish's snouts as prizes：One snout recently sold for nearly $ 1，600 online．In some Asian cultures，the toothy snouts are used in ceremonies to drive evil and disease away．And sawfish are also delicious．A growing demand in Asia for the fish's fins for a pricey soup has contributed to the fish's loves．Compared with other fish，sawfish give birth late in life and at slow rates，which makes it hard for them to recover from overfishing．
New efforts now aim to restore sawfish population．Beginning next month，an international agreement will provide protection for all seven of the world's sawfish species．Scientists are hoping that it's not too late to save the sawfish．
Until 1998，"this fish had never been formally studied in the United States，"says Tonya Wiley of the Mote Marine Laboratory in Sarasota，Fla．"We didn't know such basic things as where they live，what habitat they use，how often they breed，how many young they have-even what age sawfish are when they begin breeding．"
Through historical studies and field research，scientists have become aware of how much the fish's numbers have decreased．Today，there may be 90 percent fewer sawfish than there used to be．Wiley estimates that only 3，000 to 6，000 sawfish remain in US waters．
Sawfish
Sawfish are food hunters of the sea．When a sawfish is hungry，it waves its sharp-toothed snout （口鼻部） through a group of fish．Then，it lifts its nose and uses its mouth to draw the injured victims．
Hardy （适应力强的） population of sawfish thrived in warm waters along coastlines around the world for thousands of years．Over the past 200 years，however，human actions have severely endangered sawfish．Threats include fishing nets that trap the huge animals，often by mistake．
Some people collect sawfish's snouts as prizes：One snout recently sold for nearly $ 1，600 online．In some Asian cultures，the toothy snouts are used in ceremonies to drive evil and disease away．And sawfish are also delicious．A growing demand in Asia for the fish's fins for a pricey soup has contributed to the fish's loves．Compared with other fish，sawfish give birth late in life and at slow rates，which makes it hard for them to recover from overfishing．
New efforts now aim to restore sawfish population．Beginning next month，an international agreement will provide protection for all seven of the world's sawfish species．Scientists are hoping that it's not too late to save the sawfish．
Until 1998，"this fish had never been formally studied in the United States，"says Tonya Wiley of the Mote Marine Laboratory in Sarasota，Fla．"We didn't know such basic things as where they live，what habitat they use，how often they breed，how many young they have-even what age sawfish are when they begin breeding．"
Through historical studies and field research，scientists have become aware of how much the fish's numbers have decreased．Today，there may be 90 percent fewer sawfish than there used to be．Wiley estimates that only 3，000 to 6，000 sawfish remain in US waters．
Sawfish
| Size | over （71）6 meters long． | |
| Appearance | Body：（72）Flat and wingedNose：Like a chainsaw | |
| （73）Steps/Ways of hunting for food | Attacking fish with （74）its sharp-toothed snout． | |
| Drawing the injured victims with its mouth． | ||
| （75）Factors/Reasons/Causesof Sawfish's disappearance | （76）People's fish-catching activities/Human actions | |
| Sawfish's snout relates business． | ||
| Its （77）giving birth/breeding late and slowly which makes it hard to recover from overfishing． | ||
| （78）Present/Today's situation | Only 10% sawfish left | |
| 3，000 to 6，000 remain in US waters | ||
| Efforts | （79）Aim/Goal/Purpose | Restoring sawfish population |
| Measure | （80）Providing protection for all seven of the world's sawfish species | |
9．He is only too ready to help others，seldom，_____，refusing them when they turn to him．（ ）
| A． | if not | B． | if never | C． | if any | D． | if ever |