SAN FRANCISCO—A phone app (应用程序) in San Francisco gives information about open parking spots. City officials in San Francisco introduced the app to try to reduce traffic jams in the city, but some say it raises safety concerns. In this city, drivers searching for parking spots lead to 30 percent of all downtown jams, city officials think. Now San Francisco has found a solution—a phone app for spot-seekers that displays information about areas with available spaces. The system, introduced last month, relies on wireless sensors (感应器) fixed in streets and city garages that can tell within seconds if a spot has opened up. Monique Soltani, a TV reporter, said she and her sister spent 25 minutes on Friday trying to park. “We were praying to the parking god that we’d find a spot,” she said. “If we had the app, we would not have to pray to the parking god.” But the system could come with serious consequences. Some people say that drivers searching for parking could end up focusing on their phones, not the road. “It could be really distracting (使分心的),” said Daniel Simons, a professor of psychology at the University of Illinois. City officials acknowledge the potential problem. They are urging drivers to pull over before they use the city’s iPhone app, or to do so before they leave home. Nathaniel Ford, executive director of the San Francisco Municipal Transportation Agency, said safety could actually improve if drivers quickly found a spot instead of circling and getting frustrated. San Francisco has put sensors into 7,000 parking spots and 12,250 spots in city garages. If spaces in an area open up, the sensors communicate wirelessly with computers that in turn make the information available to app users within a minute, said Mr. Ford, of the transportation agency. On the app, a map shows which blocks have lots of places (blue) and which are full (red). More than 12,000 people have downloaded San Francisco’s app, which is available now only for the iPhone but which city officials say they hope to bring to all similar devices. When it is started up, the city’s parking app warns drivers not to use the system while in motion. But safety advocates said that might not be sufficient. After all, they say, texting while driving is illegal in California and in many states, but a number of surveys, including one by the Pew Research Center, show that many Americans do it anyway. Elizabeth Stampe, executive director of Walk San Francisco, a pedestrian advocacy group, said she hoped the new parking app would lead to fewer accidents. “It’s an innovative idea,” she said. “The safe way for people to use the device is for them to pull over, which they know they should do. The question is whether they will.” But Ms. Soltani, the TV reporter, said using the app would probably join the group of activities already performed by drivers. “We’re already looking at Google Maps and Facebook on the phone while we drive,” she said. “Aren’t we always looking at something on our phone, or changing the radio, or drinking coffee? You’re always slightly distracted when you’re driving.” 小题1:What is the phone app mentioned in the text mainly aimed at? A．Making full use of the parking spots. B．Making the traffic flow smoothly. C．Preventing traffic accidents. D．Benefiting iPhone users. 小题2:According to the text, San Francisco city officials ______. A．don’t consider the app distracting B．advise drivers to park cars slowly C．are aware of the app’s disadvantages D．believe more parking spots are needed 小题3:How do drivers locate the parking spots? A．Sensors'computers'app. B．App'computers'sensors. C．Sensors'app'computers. D．Computers'app'sensors. 小题4:The phone app mentioned in the text ______. A．is a bit slow in reacting B．hasn’t been put into service C．was introduced several years ago D．can’t be downloaded to all phones 小题5:Which of the following is TRUE according to the text? A．Daniel Simons thinks the app convenient. B．San Francisco will put more sensors into use. C．Most drivers open the app once they start their cars. D．Nathaniel Ford doesn’t doubt the practical use of the app.