Student or Learner
I might have misheard it but I think it was "We are going to take the up-train straight home." The train that is going uptown?
In my youth, the up train was heading into London, the down train from there. I don't know if these terms are still used in this way today.
I've never heard of an up train or down train before.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
I suspect these expressions went out with bowler hats and rolled umbrellas.
By the way, my offspring mock me if they hear me say, "I went up in 64". Going up and coming down with the meaning of going to university are probably dead and buried now, but they were not uncommon into the 1970s, particularly if the university was Oxford or Cambridge, or my would-be Oxbridge alma mater, Durham.