* Verb (present participle): This is the most common use. Example: "The cat is hiding under the bed."
* Gerund: This is when it functions as a noun. Example: "Hiding is a good strategy when you're playing tag."
* Adjective: This is less common, but possible. Example: "The hiding place was perfect for the treasure."
To determine the correct part of speech, you need to look at the sentence structure and how "hiding" is functioning.