9、手机拍摄照片属于数字图像 Photos taken by mobile phones belong to digital images.
9、手机拍摄照片属于数字图像 Photos taken by mobile phones belong to digital images.
参考答案和解析
D
相关考题：
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to, retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.People buy cell phones for the following reasons EXCEPT that_______________.A:they're popularB:they're usefulC:they're convenient D:they're cheap
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to, retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The word"detected"in Paragraph 3 could be best replaced by______________.A:curedB:removedC:causedD:discovered
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to, retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.On the safety issue of mobile phones,the manufacturing companies______________.A:deny the existence of mobile phone radiationB:develop new technology to reduce mobile phone radiationC:try to prove that mobile phones are not harmful to healthD:hold that the amount of radiation is too small to worry about
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to, retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The writer's purpose of writing this article is to advise people______________.A:to buy mobile phonesB:to update regular phonesC:to stop using mobile phones D:to use mobile phones less often
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to, retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The salesman retired young because_______________.A:he disliked using mobile phonesB:he couldn't remember simple tasksC:he was tired of talking on his mobile phoneD:his employer's doctor persuaded him to
共用题干第二篇Cell Phones : Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case,a traveling salesman had to retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years. His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The writer's purpose of writing this article is to advise people_________.A:to buy mobile phonesB:to use mobile phones less oftenC:to update regular phones D:to stop using mobile phones
共用题干第二篇Cell Phones : Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case,a traveling salesman had to retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years. His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.People buy cell phones for the following reasons EXCEPT that_________.A:they're popularB:they're usefulC:they're cheapD:they're convenient
共用题干Can Mobile Phones Cause Disease?1 "Mobile phone killed my man,"screamed one headline last year.Also came claimsthat an unpublished study had found that mobile phones cause memory loss.And a British newspaper devoted its front page to a picture supposedly（假定地）showing how mobile phones heat the brain.2 For anyone who uses a mobile phone,these are worrying times.But speak to the scientists whose work is the focus of these scares and you will hear a different story.According to them, there is no evidence that mobile phones cause cancer or any other illness in people.3 What we do have,however,are some results suggesting that mobile phones' emissions have a variety of strange effects on living tissue that can't be explained by the general radiation biology.And it's only when the questions raised by these experiments are answered that we'll be able to say for sure what mobile phones might be doing to the head.4 One of the odd effects comes from the now famous"memory loss"study.Alan Preece and his colleagues at the University of Bristol placed a device that imitated the microwave emissions of mobile phones to the left ear of volunteers.The volunteers were just as good at recalling words and pictures they had been shown on a computer screen whether or not the device was switched on.Preece says he still can't comment on the effects of using a mobile phone for years on end.But he rules out the suggestion that mobile phones have an immediate effect on our cognitive abilities."I'm pretty sure there is no effect on short-term memory,"he says.5 Another expert,Tattersall,remarked that his latest findings have removed fears about memory loss.One result, for instance, suggests that nerve cell synapses（突触） exposed to microwaves become more-rather than less-receptive（感受的）to undergoing changes linked to memory formation.6 Hopefully,microwaves might turn out to be good for you.It sounds crazy,but a couple of years ago a team led by William Adey at the Veterans Affairs Medical Center in California, found that mice exposed to microwaves for two hours a day were less likely to develop brain tumours when given a cancer-causing chemical.Tattersall said for sure that the________over memory loss caused by mobile phones was ungrounded.A:difterent messagesB:is hopedC:public attentionD:solid evidenceE:attracted public attentionF:public anxiety
共用题干第二篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case,a traveling salesman had to retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years. His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The writer's purpose of writing this article is to advise people___________.A:to buy mobile phonesB:to stop using mobile phonesC:to update regular phonesD:to use mobile phones less often
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today,In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with Young people.They find that the phones aremore than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mnobile phone only when you really need it.Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The word"detected"in Paragraph 3 could be best replaced by_________.A:curedB:removedC:discoveredD:caused
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today,In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with Young people.They find that the phones aremore than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mnobile phone only when you really need it.Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The writer's purpose of writing this article is to advise people__________.A:to use mobile phones less often B:to buy mobile phonesC:to update regular phonesD:to stop using mobile phones
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today,In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with Young people.They find that the phones aremore than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mnobile phone only when you really need it.Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.People buy cell phones for the following reasons EXCEPT that________.A:they're popular B:they're cheapC:they're useful D:they're convenient
共用题干Can Mobile Phones Cause Disease?1 "Mobile phone killed my man,"screamed one headline last year.Also came claimsthat an unpublished study had found that mobile phones cause memory loss.And a Britishnewspaper devoted its front page to a picture supposedly（假定地）showing how mobilephones heat the brain.2 For anyone who uses a mobile phone,these are worrying times.But speak to the scientists whose work is the focus of these scares and you will hear a different story.According to them, there is no evidence that mobile phones cause cancer or any other illness in people.3 What we do have,however, are some results suggesting that mobile phones' emissions have a variety of strange effects on living tissue that can't be explained by thegeneral radiation biology.And it's only when the questions raised by these experiments are answered that we'll be able to say for sure what mobile phones might be doing to the head.4 One of the odd effects comes from the now famous"memory loss" study.Alan Preeceand his colleagues at the University of Bristol placed a device that imitated the microwave emissions of mobile phones to the left ear of volunteers.The volunteers were just as good at recalling words and pictures they had been shown on a computer screen whether or notthe device was switched on.Preece says he still can't comment on the Effects of using a mobile phone for years on end.But he rules out the suggestion that mobile phones have an immediate effect on our cognitive abilities." I'm pretty sure there is no effect on short-termmemory,"he says.5 Another expert,Tattersall,remarked that his latest findings have removed fears about memory loss.One result, for instance, suggests that nerve cell synapses（突触） exposed to microwaves become more一rather than less一receptive（感受的）to undergoing changes linked to memory formation.6 Hopefully,microwaves might turn out to be good for you.It sounds crazy,but a couple of years ago a team led by William Adey at the Veterans Affairs Medical Center in California found that mice exposed to microwaves for two hours a day were less likely to develop brain tumours when given a cancer-causing chemical.The safety problem with mobile phones has_________.A:different messagesB:is hopedC:public attentionD:solid evidenceE:attracted public attentionF:public anxiety
共用题干第一篇Cell Phones: Hang Up or Keep Talking?Millions of people are using cell phones today,In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with Young people.They find that the phones aremore than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to retire at a young age because of serious memory loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man used to talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mnobile phone only when you really need it.Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The salesman retired young because____________.A:he disliked using mobile phonesB:he couldn't remember simple tasksC:he was tired of talking on his mobile phone D:his employer's doctor persuaded him to
问答题Topic 2：My View on College Students’ Use of Mobile Phones Questions for reference: 1) What is the phenomenon of college students’ using mobile phones? 2) What might be the advantages and disadvantages of their using mobile phones? 3) What could be done to this problem?
单选题It can be inferred that the attitude of the WHO and the British government toward the use of mobile phones is ______.AprecautiousBskepticalCapproving
单选题What is the speaker’s main topic?AEffects of using mobile phones on healthy human cells.BRisks of developing cancer involved in the use of mobile phones.CDamage to healthy cells caused by the use of mobile phones.DThe potential health hazards of mobile phones on humans.
单选题According to the passage, which of the following statements is NOT true?AThe potential health hazards of mobile phones call for further research.BThe Australian scientists find no connection between growth of tumors in human body and radiation from mobile phones.CThe Italian scientists’ belief is shared by other scientists.DThe British government inquiry didn’t establish any link between health risks and use of mobile phones.
单选题The author implies that the use of mobile phones in such places as museums should be _____.AlimitedBdiscouragedCexpectedDrecommended
单选题We ______ use mobile phones when the plane takes off.Amay notBshouldn’tCneedn’tDmustn’t