1.  Planners insist that the trains will run quietly and use less energy than any other means of transportation, including conventional trains.

2.  A conventional Amtrak train was sent out in its place.

3.  Amtrak will continue to offer less expensive fares aboard conventional trains.

4.  Freight shipments, including large trucks, are hauled through the tunnel on more conventional trains.

5.  Maglev trains differ from conventional trains in that magnets lift them slightly off the ground, eliminating friction with the tracks.

6.  Maglev trains differ from conventional trains in that magnets lift them slightly off the ground, eliminating speed-reducing friction with the tracks.

7.  Problems with the tilting technology that helps the train negotiate curves at higher speeds than conventional trains caused a series of delays.

8.  So the railway brought in a conventional Metroliner train for the Washington-to-Boston run, but the bad news continued.

9.  Unlike conventional trains, the trains have magnets that lift them slightly off the track, eliminating the friction that normally occurs when wheels hit track.

10.  The United States has experimented with different rail systems, attempting to adapt some European models that are faster than conventional trains to existing US tracks.