There are a few things to consider when writing an acknowledgement in a poetry book. First, you will want to thank anyone who helped with the creation or publication of the book. This could include your publisher, editor, and any beta readers or proofreaders. You may also want to thank anyone who inspired you or influenced your work, such as a favorite poet or a teacher. Finally, you may want to say a few words about why you wrote the book or what it means to you.
Here is an example of an acknowledgement from a poetry book:
"First and foremost, I would like to thank my publisher, editor, and beta readers for all their hard work in making this book a reality. I would also like to thank my favorite poets, who have influenced my work and inspired me to keep writing. Finally, I want to say a few words about why I wrote this book. For me, poetry is a way to express the emotions and experiences that are too difficult to put into words. It is a way to connect with others and to understand the world around us. I hope that my poetry can provide solace and comfort to those who need it."