真的很耗油?

The Senate's bill would increase the average standard for new vehicles to 35 miles per gallon by 2020 from the current 25mpg—a target that would require improvements for light trucks and sport-utility vehicles as well as cars. But in the House, fuel economy is the domain of the Energy and Commerce committee, which is chaired by John Dingell, a congressman from Michigan who is a firm friend of the car industry. America's troubled carmakers insist that 35 mpg is unattainable, although the National Academies of Science says it is possible. Vehicles in Europe and Japan already exceed that level.

it really depends on the performance and the road condition

a 1.6 liter engine would be able to obtain 35mpg much easier than a 3.0 liter. in europe and japan, most cars are with small engine capacity, thus slow acceleration and less drag power etc. in america, people are used to carry a boat, a trailer or even a house-truck with the car... it would be impossible for a 1.6 liter engine to be popular here if Americans don't change the life style...

Gas consumption has nothing to do with nationality.

It is always a trade-off between performance and gas economy. I cannot imagine a Mercedes ML63 AMG getting 35mpg, unless it does not use gas any more.