Strangely,some people find that they can smell one type of flower but not another,（ ）others are sensitive to the smells of both flowers.A.whenB.sinceC.forD.whereas
Strangely,some people find that they can smell one type of flower but not another,（ ）others are sensitive to the smells of both flowers.
A.when
B.since
C.for
D.whereas
B.since
C.for
D.whereas
参考解析
解析：本题考查的也是对空格前后的两个半句之间的逻辑关系的理解。由于上半句提到“有些人认为他们可以闻出一种花香，却闻不出另一种”，下半句提到“有些人却对两种花香都很敏感”。显然这两个半句之间构成一种对比关系，而选项A.when用于引导时间状语从语，B.since用于引导时间或原因状语从句，C.for用于引导原因状语从句，都不符合上下文语义关系。只有D.whereas可用于引导表示转折关系的并列句，符合上下文逻辑语义关系，因此，本题的正确选项是D
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In some libraries young people can check out ten juvenile books at one time.A:adventureB:large-printC:hardcoverD:children's
共用题干第二篇Study Says Dogs Can Smell CancerDogs are known for their sense of smell.They can find missing people and things like bombs and illegal drugs.Now a study suggests that the animal known as man's best friend can even find bladder（膀胱）cancer.Cancer cells are thought to produce chemicals with unusual odors（气味）. Researchers think dogs have the ability to smell these odors,even in very small amounts,in urine（尿）.The sense of smell in dogs is thousands of times better than in humans.The study follows reports of cases where,for example,a dog showed great interest in a growth on the leg of its owner.The mole（痣）was later found to be skin cancer.Carolyn Willis led a team of researchers at Arnersham Hospital in England.They trained different kinds of dogs for the experiment.The study involved urine collected from biadder cancer patients,from people with other diseases and from healthy people.Each dog was tested eight times.In each test there were seven samples for the dogs to smell.The dog was supposed to signal the one from a bladder cancer patient by lying down next to it,Two cocker spaniels（短腿长毛垂耳小猎犬）were correct fifty-six percent of the time.But the scientists reported an average success rate of forty-one percent.As a group,the study found that the dogs chose the correct sample twenty-two out of fifty-four times.That is almost three times more often than would be expected by chance alone.The British Medical Journal published the research.In all,thirty-six bladder cancer patients and one hundred and eight other people took part.During training,all the dogs reportedly even identified a cancer in a person who had tested healthy before the study,Doctors found a growth on the person's right kidney(肾）.Bladder cancer is the ninth most common cancer worldwide.The International Agency for Research on Cancer says this disease kills more than one hundred thousand people each year.Doctors say cigarette smoking is the leading cause of bladder cancer. Participants in the experiment wereA:36 bladder cancer patients. B:144 cancer patients.C:1 08 healthy people. D:144 sick and healthy people.
A stream of voice packets transmitted over a WAN network encounters differing queuing delays. One router in the path used by the voice packets delays some of the packets for 4 ms while transmitting a large video file， but delays other packets only 2 ms. Another router delays some packets 5 ms， but transmits others in 2 ms. How would you best describe this type of problem？（）A、end-to-end delayB、interference from bulk data trafficC、processing delaysD、serialization delaysE、jitter
单选题A stream of voice packets transmitted over a WAN network encounters differing queuing delays. One router in the path used by the voice packets delays some of the packets for 4 ms while transmitting a large video file， but delays other packets only 2 ms. Another router delays some packets 5 ms， but transmits others in 2 ms. How would you best describe this type of problem？（）Aend-to-end delayBinterference from bulk data trafficCprocessing delaysDserialization delaysEjitter
单选题Research into customer satisfaction showed that ______.Athe right smell made people think a product was betterBpeople preferred the smell of lemon to coconutCcertain smells could make people dislike a shopDcustomers rated the goods on sale as more inviting
单选题Some people are often surprised by what other people do. According to Berger, that is mainly because _____.Asome people are more emotional than othersBsome people are not aware of the fact that we will never completely know another personCsome people are sensitive enough to sense the change of other people’s attitudesDsome people choose to keep to themselves
单选题As indicated in the passage, being free personal preference in that _____.Ameans that one can ignore other people’s criticismBmeans that one can impose his preferences on othersCdoesn’t mean that one has the right to do things at willDdoesn’t mean that one has the right to charge others without evidence
问答题◆Topic 7：TV—the Pandora’s Box to Children? Questions for Reference: 1) Some people think children’s spending time on TV and video is good, while others think it is bad. Discuss both views. 2) Give your own opinion about this issue. 3) What can we do to ensure the TV and video make a positive effect on our children?
单选题What type of constraint can be used to ensure that, in any given row in a table, the value of one column never exceeds the value of another column?（）ACheckBRangeCReferentialDInformational