comma with 'which': world's highest swimming pool, which one can find


New Member
Polish - Poland

I've been having problems deciding whether or not to insert a comma in the following sentence (red):

'Not only is it the most daring undertaking of engineering to date, but it has also set a variety of different records, including the highest numbers of floors, the tallest structure ever built (curiously enough, it was Warsaw Radio Mast which had held this title until the tower of Khalifa came into play six years ago) or even the world’s highest swimming pool, which one can find as high as on the 144th floor.'

According to the guide I've found on the Internet ( we do not use commas when 'who' or 'which' clause identifies which ones we are talking about. But then again, in this case, the second clause might be considered to be an extra information WHILE identifying the one I mean. (which one? - the one which you can find as as on the 144th floor, BUT without this detailed information, the sentence still makes sense). So what would be the difference between the bolded phrase with and without comma?

ps: forgive all punctuation mistakes that i've made, i'm still yet to go through the entire article :)
  • Italian
    Hullo, bushio.

    The portion [, which one can find as high as on the 144th floor.] is not required for the identification of the tower, which is already identified by means of the qualifier [world’s highest].

    [, which one can find as high as on the 144th floor.] is indeed extra information, hence the use of a comma.




    post mod (English Only / Latin)
    English - US
    I agree that the comma is needed.
    Without the comma, it would mean that there are other pools on the 144th floor, but this is the highest one.

    You can find previous threads discussing the use of the comma after 'which' by clicking this link: comma relative pronoun which