“Visitors tothe 2010 World Expo（世博会） in Shanghai will be able to gosightseeing in super cool cars with no drivers,” Shanghai city governmentspeaker said recently（近期）.   When the six-seat car was shown to the public（公众）, itinterested many people. “The car will help visitors feel what high technology（技术）is and helpthem enjoy the tour of the World Expo site,” said a teacher from TongjiUniversity. The car, 4.5 meters long, 1.7 meters wide（宽）, and 1.6meters tall, runs along a white line. The car costs around 300,000 >yuan to build and can reach a top speedof 50 kilometers per hour.   According to the researches（调查）, visitorswill be able to drive the car anywhere in the World Expo site by pressing abutton（按钮）. If they want to get off or stop the car, all they need to dois just to press the button again.   “People can rent （租赁）one of thesecars for a whole day or just take a ride in it from one place to another,” theteacher said. About 400 to 500 of these cars will be made for the Expo in 2010.the cars will have a radar（雷达）to help themget around. They will mainly use solar（太阳能）batteries. Andthey have no need of drivers and oil（汽油）, these carswill help save energy and human work, and cause no pollution to the environment.