11.   Some concern has been raised that trains could be used to deliver such attacks.

12.   The new trains will be used on Acela Express routes, while Acela Regional and Acela Commuter will use refurbished cars.

13.   While not used as extensively as cars or planes, trains are used far more in Europe than the United States.

14.   If trains are primarily used, there could be two train shipments each week and one truck shipment every five or six days.

15.   In some areas of the country, passengers were using trains.

16.   Major roads around large cities were jammed with motorists who could not use trains.

17.   Millions of Japanese visit South Korea annually but they seldom use trains in South Korea, Yang said.

18.   More people have been using the train since El Nino rains last year washed out portions of the Nairobi-Mombasa highway.

19.   Riders were resigned to having to use the train, even if they are still frightened.

20.   Riders were resigned to having to use the train Wednesday, even if they were still frightened.