Have you ever seen a car without a driver？It sounds crazy，but these computer﹣driven driverless cars will soon be filling roads near you．Companies like Google and Tesla have been designing and testing these cars，and the technology is there．

So how？The cars have sensors（感应器） all around which can find other cars and objects in the road．Road signs are read by cameras，and satellite navigation systems（卫星导航系统） are used so the car knows how to get where you want to go．All you have to do is type in the address! Finally，a central computer system takes in all the information that it receives from the sensors and cameras and works out when to speed up，stop and turn．

Sound like your idea of heaven（天堂）？Sitting back，looking out of the windows and even watching a film or reading a book while "driving" would be possible with this new technology．You wouldn't have to worry about remembering directions to where you're going．In addition，computers would also drive more safely than people﹣they would obey the rules and have quicker action times when in dangerous situations．

However，there are many drawbacks of driverless cars．Computers would have difficulties making ethical（道德的） decisions：if a child ran into the road，would the computer choose to hit the child or turn suddenly and potentially kill the car's passengers？Moreover，I personally find driving fun﹣I'd miss never driving a car myself．There would also be many other decisions to be made﹣should children，or drunk people，be allowed in a driverless car by themselves？Or would there need to be a person with a driving license in the car at all times？

I'm not certain．I'd want a driverless car﹣but it's only a matter of time before they'll become more affordable and popular on our roads．

42．When using a driverless car，you need only 　　．

A．read the road signs carefully         

B．check the cameras

C．put the address into the computer      

D．remember the directions

43．The third paragraph mainly tells us about the 　　of driverless cars．

A．instructions        

B．standards          

C．advantages     

D．tests

44．The underlined word "potentially" in Paragraph 4 means"　　"．

A．possibly         

B．successfully        

C．especially      

D．naturally．

45．What's the writer's opinion about future driverless cars？

A．They'll cause more accidents．

B．They'll be less expensive．

C．They'll use less energy．

D．They'll run much faster．