Student or Learner
Hi, please read the below paragraph. I don't understand the underlined
part. I'd like to know what the underlined part mean in this context.
And I think "unless" needs to be changed to "if" in order to maintain
the flow. What do you think?
The distance between the rails of a railway track is called the gauge. About
60 percent of the world's railways are standard gauge, which is 1,435
meters. A few tracks have a narrower gauge. When you read the names on
the cars of a long freight train, you are surprised how many different railways
are represented. This would not be possible unless the cars were built for
tracks of standard gauge.
No, 'unless' has the oppposite meaning to 'if'. The tracks are standard, so cars from many different railways can use the same tracks. Therefore, one train often pulls cars belonging to a surprisingly large number of different railway companies. The names of these companies are written on each of the cars that belong to them.