I wrote it this way in my manuscript:

We construct a 25-order planar graph with minimum degree 4.

My grammar checker (languagetool.jar) is reminding me to use "an" instead of "a." I'm a bit unsure, so I'm asking here. enter image description here

I suspect the reason could be that the grammar checker doesn't recognize "25" and instead directly recognizes "order."

I'm not sure if the issue is with this software or if it's related to using "number-noun" constructions (as there might be specific rules regarding this).

  • 1
    Whether to use "a" or "an" will depend on how you pronounce "25". If you say "twenty-five", then use "a". Maybe languagetool had in mind some other pronunciation...
    – GEdgar
    Aug 26, 2023 at 9:14
  • 1
    @GEdgar is there a different way of pronouncing "25"?
    – Mari-Lou A
    Aug 26, 2023 at 9:59
  • 1
    @AndrewLeach This question is closed as a duplicate of two older questions but the number 1100 does indeed have two different pronunciations: "one thousand (and) one hundred" OR "Eleven hundred". What other way can 25-order be pronounced?
    – Mari-Lou A
    Aug 26, 2023 at 11:45
  • 2
    @AndrewLeach Whether said as "twenty-five" or as "two-five" or as "twenty-fifth" or any other permutation, the initial "t" does not change, nor should the "a" be changed to an "an." This is not an initial vowel that could change depending on its pronunciation, nor is it an "h" or any other letter that might be silent.
    – Biblasia
    Aug 26, 2023 at 12:09
  • 1
    Using 'an' here is wrong, plain and simple. The choice is determined by pronunciation of the following entity alone (with one or two grey areas with words like hotel / historic, and where what follows is open to differing pronunciations (eg FAQ) or even readings). Aug 26, 2023 at 14:12


Browse other questions tagged or ask your own question.