For Group C cars is 6 pounds per day.
出自-2014年6月听力原文
By 1973, domestic US sources of oil were peaking, and the nation was importing more of its oil, depending on a constant flow from abroad to keep cars on the road and machines running.
出自-2013年6月阅读原文
The technology has been successfully applied overseas, but the only other public robotic garage in the United States has been troublesome, dropping vehicles and trapping cars because of technical problems.
出自-2013年6月听力原文