posted by John .
One day Minsu and Cathy were on the subway. The subway stopped. An old couple got in.
(In the passage, is 'subway' used properly? Do we have to use 'train' instead of 'subway' in this case?)
The train stopped. (the subway did not stop.) It would be better to combine the short sentences into a longer one.
Anonymous' idea about taking two simple sentences and combining them into a complex one is a good one. But, of course, the subway would have to stop, or no one else could get on. Yes, there is a difference between a train (that usually runs above ground) and a subway (that usually runs below ground.)