* Marshy body of water: This could be described as a swamp, bog, marsh, or wetland.
* Contains a pronoun: This is where things get interesting. Pronouns are words that replace nouns. The only way a marshy body of water could "contain" a pronoun is if it's a figurative use of the word.
Here are some possible interpretations:
* A marsh that is *described* by a pronoun: For example, "It was a desolate marsh." Here, "it" is a pronoun referring to the marsh.
* A marsh that is *personified* and *speaks*, using pronouns: This would be a literary device where the marsh is given human-like qualities.
Let me know if you have more context for your request, and I might be able to give you a more specific answer.