Say that I am giving an introductory clause with a list of things, using the colon. If I also use a secondary clause, by way of a comma to explain the first clause, do I separate the comma and colon with a space?


The following items are needed to start the project, which are very important at the beginning,: pencils, pens, etc.

  • Since the question was answered, what needs to change so the reviewers will vote to re-open it? Aug 27, 2022 at 6:52
  • A question can still be answered even if it is closeworthy. This question would (in my view, and another moderator's) be better on English Language Learners, but they rejected it for lack of research, and three reviewers have voted to keep the question closed. The answer addresses all aspects of your sentence, the most important of which is that the relative clause is misplaced. It also addresses the custom that two punctuation marks very very rarely appear together.
    – Andrew Leach
    Aug 28, 2022 at 7:26

1 Answer 1


You would omit the comma.

That said, you're not ending the sentence in your example with a comma. That sentence ends with a period: the period after "etc."

Also, as it relates to the example, your question is moot since the relative clause is misplaced. Since the relative clause "which are very important at the beginning" modifies "items," it must immediately follow "items" (i.e., The following items, which are very important at the beginning, are needed to start the project: pencils, pens, etc.). Placing it after "project" makes it, as a matter of grammar, a misplaced modifier since placing it after "project" makes it modify "project" instead of "items," or seem to.

  • I replaced "sentence" with "clause", so that the clause ends in a colon/comma. So, what you are saying is that my "explanatory" clause should be placed elsewhere. Nevertheless, can you give a better example where the secondary/relative clause would correctly occur after the primary clause, both clauses are separated by a comma but the colon (signifying the list) comes after the secondary/relative clause? Or such a construction wouldnt occur? Aug 24, 2022 at 8:21
  • I actually answered your question in my first sentence. If you'd provided an example where a subordinate clause immediately preceded the colon appropriately, as I said, "You would omit the comma." Just like you never put a comma right next to a semicolon, period, or any other clause- or sentence-ending punctuation, you never put one before a colon, either. If some other punctuation is called for, then it replaces the comma, which is why you will never see ",:" or ",?" or ",." or ",!" or ",;" in properly written English. Aug 24, 2022 at 17:13
  • Now, ",—" I have seen, but only in writings by Keats and Shakespeare, which are centuries old and which by today's standards wouldn't be grammatical, except maybe if written by a poet or playwright in a work since artistic license generally gives them a lot wider berth, meaning if Keats and Shakespeare were alive today and wrote that, they'd still easily get away with it. That said, unless you're a poet or playwright who has the clout of Keats or Shakespeare and are writing a magnum opus, you'd do well to stear clear of such grammatical embellishments. Aug 24, 2022 at 17:30

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