GRE作文新增的argument题目(4)_GRE写作

GRE作文新增的argument题目(4)

　　one kind of brain-scanning device is used by doctors to monitor normal as well as abnormal activity in a patients brain. the device provides precise measurements of blood flow in the brain, a known indicator of how the brain is working. unfortunately, the device requires patients to remain completely still with their heads in the scanning machine, which makes a very loud noise. under these uncomfortable conditions, it is doubtful that doctors can get accurate measurements. a new head-mounted device that measures eye movements rather than blood flow and allows patients to move around will undoubtedly provide better brain measurements. thus, the new head-mounted device should replace the older device at all hospitals and research institutions.

　　blue city highway had always been notorious for its tight curves and poor roadway visibility, and the accident rate there was generally very high. last year the highway was redesigned to broaden the curves and improve roadway visibility. drivers report that they now feel much safer driving on the highway and that the redesign has been a big improvement. but the number of accidents on the highway has not been significantly lower in the six months since the redesign than it was in the six months before the redesign. therefore, the redesign clearly did not improve the curves and roadway visibility enough to make a difference.