Some scientists warn that the X-ray _________ (scan) now being used to screen passengers at many airports may be harmful to the human body.
举一反三
- Scientists performed the first MRI body of a human being in July .
- 青书学堂: (单选题) Some scientists think that one day animals may be trained to do a number of simple jobs that are now done by human beings. Perhaps you have seen some animals doing quite skillful things at a circus. If you watch closely, you may notice that the trainer always gives the animal a piece of candy or a piece of fruit as a reward. The scientists say that many different animals may be trained to do a number of jobs if they know they will get a reward for doing them. Of course, as we know, dogs can be used to guard a house, and soldiers both old and modern times have used geese to give warning by making a lot of noise when a stranger or an enemy comes near. But it may be possible to train animals to work in factories. Birds with good eyesight are being used to watch out for fault in small steel balls that are being made in one factory. Apes have been used in America in helping to make cars and scientists believe that these large monkeys may be trained one day to gather crops and even drive trains. What made scientists think that animals can be trained to for us one day ?( ) (本题4.0分)
- Scientists are responsible for people who hold harmful beliefs about human nature because. A: the theories of scientists are used as justification for such harmful beliefs B: only through science can these people be refuted C: they have an obligation to correct their mistakes D: scientists are the ones who know the true nature of humankind
- Only when they are injured______. A: will some animals attack a human being B: a human being will be attacked by some animals C: some animals will attack a human being D: that some animals attack a human being
- At many international airports, passengers can buy _______ free goods such as perfume, cosmetics, liquor and souvenirs.