comma after introductory phrase [conjunction]: When listening..., I

Couch Tomato

Senior Member
Russian & Dutch
When listening to the first guy’s answer, I had to think of my young neighbour who spends most of his life working overtime in a dirty, unhealthy factory environment to show off his possessions in the few weekends he is not on duty.
(CPE sample script which can be found here)

This sentence is part of a CPE sample script. It's supposed to have minimal error and I'm trying to find possible slip-ups. I would like to know if that comma is optional or not. I feel as though we do need it. What do you think?

Thank you in advance
  • Commas are usually optional. They're optional when they separate time or place phrases from the main clause. It's a stylistic matter only - is the opening phrase so long that you need a breather? is there a possibility of misreading as a different grouping of words if it wasn't there?
    Thank you. Well, in that case it's it can be left out as the phrase isn't too long and there isn't really a possibility of misreading it. Still, I am inclined to put a comma there. Perhaps that's just a personal feeling I have.
    As a side note, since you are looking for something very elusive, I would be a lot more likely to say 'While listening...', not 'When listening...' :)