What is the subject of Please give you a book?

The sentence "Please give you a book" is grammatically incorrect and doesn't make sense.

Here's why:

* "You" is the object, not the subject. The sentence should be "Please give me a book."

* The subject is missing. The sentence needs a subject to perform the action of giving the book.

To understand the subject, we need a complete and grammatically correct sentence. For example:

* "Could you please give me a book?" - The subject is "you".

* "Please give me a book." - The subject is "you" (implied).

Let me know if you have a different sentence in mind, and I can help you identify the subject!