I came through a sentence that comma precedes "in which," but I have heard that no comma precedes "which" that has a preposition before it.

Application of Hennig’s winnow therefore supported a different cladogram , in which tarantulas and their allies (Mygalomorphae) are more closely related to typical spiders (Araneomorphae) than they are to the Liphistiidae.

In the above sentence, is comma necessary ?

  • But if you are going to use a comma, the convention is not to put a space between it and the word that precedes it. ...cladogram, in which...
    – TimR
    Commented Apr 28, 2016 at 11:50
  • It is just a typo.
    – ARYF
    Commented Apr 28, 2016 at 11:52
  • 1
    You also put a space before your question mark. The same convention applies there too. If you're going to worry about such stuff, might as well get it right.
    – TimR
    Commented Apr 28, 2016 at 11:53
  • Edit your answer and fix your typos–especially if you've made a typo in the exact thing you're asking about. Commented Apr 28, 2016 at 13:55
  • Also, please provide a link to where you found this sentence. The context could show whether a comma is necessary or not, since this could be a restrictive or non-restrictive relative clause. Commented Apr 28, 2016 at 13:57

1 Answer 1


Strictly speaking no comma is required. But because there are two fairly long clauses to the sentence, a comma between them provides a convenient separator. It does not change the meaning and is not absolutely necessary, but it makes the long sentence simpler to parse and therefore the meaning is easier to understand.

  • So are you saying that this rule applies only here or all cases of "in which"?
    – ARYF
    Commented Apr 28, 2016 at 11:50
  • There is no rule that says you must or must not use a comma before in which.
    – Charl E
    Commented Apr 28, 2016 at 12:04
  • 1
    So what should I follow?
    – ARYF
    Commented Apr 28, 2016 at 12:12

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .