Answer:
3. El libro.
4. La identificación.
Step-by-step explanation:
In this exercise you have to say what you take on vacation. For example, in my case, I usually carry a book with me just in case I want to read a novel by the lake. Another thing I usually carry with me is my identification because there are situations in which you will need your ID. So what I always carry with me are a book and my ID.