题目内容
4．_______ astonishes us is that AlphaGo defeated the human champion．（ ）| A． | Which | B． | When | C． | That | D． | What |
分析 让我们惊讶的是阿尔法围棋（智能程序）居然打败了人类冠军．
解答 答案：D 题干所给的句子中，前面的astonishes us 是谓语结构（动词用了三单形式）；后面接了is that AlphaGo defeated the human champion系表结构，说明前面的部分是充当了is的主语，是一个主语从句；主语从句中astonishes缺少主语，要用连接代词．故选D．
点评 在句子中起名词作用的各种从句统称为名词性从句．根据它们在句中的语法作用，这类从句又可分为主语从句、同位语从句、表语从句和宾语从句． 本题中what在主语从句中起连接作用，同时又充当了从句的主语．
练习册系列答案
相关题目
15．It is worth considering _______ the Korean drama Man From the Stars is so popular in China．（ ）
| A． | why | B． | whether | C． | that | D． | which |
19．He had a great desire to have a home of his own，______ he had always lived with his grandmother．（ ）
| A． | or | B． | and | C． | so | D． | for |
9．
Are Sweeteners （甜味剂） Safe and Healthy？
For many of us，the relationship we have with sugar is love at first taste，and that love usually lasts a lifetime．But what price do we have to pay for this truly addictive，sugary love？Type 2 diabetes （糖尿病）？Heavier bodies？Raised blood sugar levels？Or even（41）Gteeth？
Time to quit perhaps？Easier said than done．What's the alternative？Many would suggest using sweeteners as a（42）C．But are sweeteners healthier than sugar？
Sweeteners are usually low-calorie （卡路里） or calorie-free substances that have a similar taste to sugar．It is estimated that more than a quarter of British households buy（43）Asweeteners to help cut their sugar intake．
The European Food Safety Authority （EFSA） has（44）Jsome of the health claims food manufacturers have made about sweeteners such as xylitol，sorbitol and sucralose．These include（45）Etooth decay and controlling blood sugar levels．
According to the National Health Service in the UK，sweeteners are safe to use and are（46）Bhelpful for those who are diabetic．Sioned Quirke，a spokesperson for the British Dietetic Association says，"As a dietician，I support and promote the use of sweeteners in cooking and diet．"She also says that"There is no（47）Kto suggest that low-calorie sweeteners，such as saccharin，aspartame and sucralose，are harmful or bad for you．"
But many have（48）Fover the long-term effects caused by using sweeteners．Dr Robert Lustig，author of‘Fat Chance：The Bitter Truth About Sugar'would not accept sweeteners as an alternative to sugar because，"We lack data"．According to Dr Lustig，organisations like EFSA only require studies which test whether something will poison a person in a short period of time，which is known as acute toxicity （急性毒性） studies．But we still don't know what the（49）Heffects are．
Dietician Emma Carder says on the NHS Choices website，"While more research is needed，sweeteners continue to have a useful role in offering a sweet taste without adding（50）Dcalories．"
| A．artificial B．especially C．substitute D．extra E．preventing F．concerns G．rotten H．enduring I．inadequately J．approved K．evidence |
For many of us，the relationship we have with sugar is love at first taste，and that love usually lasts a lifetime．But what price do we have to pay for this truly addictive，sugary love？Type 2 diabetes （糖尿病）？Heavier bodies？Raised blood sugar levels？Or even（41）Gteeth？
Time to quit perhaps？Easier said than done．What's the alternative？Many would suggest using sweeteners as a（42）C．But are sweeteners healthier than sugar？
Sweeteners are usually low-calorie （卡路里） or calorie-free substances that have a similar taste to sugar．It is estimated that more than a quarter of British households buy（43）Asweeteners to help cut their sugar intake．
The European Food Safety Authority （EFSA） has（44）Jsome of the health claims food manufacturers have made about sweeteners such as xylitol，sorbitol and sucralose．These include（45）Etooth decay and controlling blood sugar levels．
According to the National Health Service in the UK，sweeteners are safe to use and are（46）Bhelpful for those who are diabetic．Sioned Quirke，a spokesperson for the British Dietetic Association says，"As a dietician，I support and promote the use of sweeteners in cooking and diet．"She also says that"There is no（47）Kto suggest that low-calorie sweeteners，such as saccharin，aspartame and sucralose，are harmful or bad for you．"
But many have（48）Fover the long-term effects caused by using sweeteners．Dr Robert Lustig，author of‘Fat Chance：The Bitter Truth About Sugar'would not accept sweeteners as an alternative to sugar because，"We lack data"．According to Dr Lustig，organisations like EFSA only require studies which test whether something will poison a person in a short period of time，which is known as acute toxicity （急性毒性） studies．But we still don't know what the（49）Heffects are．
Dietician Emma Carder says on the NHS Choices website，"While more research is needed，sweeteners continue to have a useful role in offering a sweet taste without adding（50）Dcalories．"