Annette seems to have focused on your use of the word apposite, and appears to not understand your sentence. My guess is that she isn't familiar with the use of abandon as a noun. But she is correct that as you have used it, characteristic here is an an adjective, not a noun. Your sentence is fine - and since it isn't an apposite, I don't think you should use a comma.

Thank you very much, everyone. I misunderstood the part of speech of the word 'characteristic' in the sentence, as you have said, it is a adjective rather than a noun. Now the confusion is solved! Thank you!

I understand your sentence, including the use of abandon as a noun, and agree with Gary that it doesn't need a comma.

To simplify things, apposition can be thought of as "parallelism". It means two parts of a sentence are in parallel, playing the same function relative to the rest of the sentence. So even if one of them is removed, the sentence still makes sense and remains grammatically correct. For example: - The principle, a thin man, started to speak. - "the principle" and "a thin man" are subjects in apposition. - It pointed to one fact, his incompetence. - "one fact" and "his incompetence" are prepositional objects in apposition. In both cases above, the sentence will still make sense even if one of the two apposite parts is removed. In your example, "characteristic of rabbits" belongs to "that promiscuous abandon" with no relation to any other part of the sentence. It is not appositive at all, so placing a comma is not necessary.

Commas with Appositives. The definition of an appositive is a word or word group that defines or further identifies the noun or noun phrase preceding it. Rule: When an appositive is essential to the meaning of the noun it belongs to, don't use commas. Having said that, an appositive is a noun or noun phrase that renames another noun right beside it. The appositive can be a short or long combination of words. Look at these appositive examples, all of which rename insect: The insect, a cockroach, is crawling across the kitchen table. Your sentence does not make any sense. so that it multiplied with that promiscuous abandon characteristic of rabbits. - I mean, 'characteristic of rabbits' should be appositive of 'promiscuous abandon'. An appositive is suppose to be a NOUN or a NOUN phrase. You are using adjectives. I think what you might be trying to say is this: It multiplied with promiscuous abandonment which is characteristic of rabbits. It is NOT an appositive. Let me know if I got close to what you are trying to say.