单选题
For how long has the Robot Trade Fair been held in Japan?
【正确答案】
C
【答案解析】[听力原文]
Japan has long been a leader in the development of robot technology. Robots have been used to build Japanese cars for over thirty years.
Every year Japanese manufacturers of robots show off their wares at a trade fair in Tokyo. This year, at the twentieth annual show, there were a few surprises.Surgeons may soon be using a robotic device to aid in micro-surgery. The robot surgeon can do incredibly precise work, stitching up the thinnest veins. Dentists may soon get help from robots too;
a company displayed a robotic device that may some day be used to clean teeth and even fill cavities.
One company unveiled a robotic night watchman that can patrol sensitive areas and detect any intruders—and never falls asleep! And children who attended the fair were delighted by a lifelike robotic cat that chases a robotic mouse.