What part of speech is the word sentences?

The word "sentences" can be several parts of speech depending on its context:

* Noun: When referring to the grammatical structures themselves. Example: "He wrote several long sentences."

* Verb: When referring to the act of passing a judgment or giving a punishment. Example: "The judge sentenced the criminal to five years in prison."

Let me know if you have a specific sentence in mind, and I can help you determine the part of speech!