What is the simple predicate in sentence shoes have been existence for many centuries?

The simple predicate in the sentence "Shoes have been in existence for many centuries" is have been.

Here's why:

* Predicate: The predicate is the part of the sentence that tells us what the subject does or is. In this case, it tells us about the state of shoes.

* Simple Predicate: The simple predicate is the verb or verb phrase that forms the core of the predicate. Here, the verb phrase "have been" is the simple predicate because it directly tells us about the state of the shoes ("have been in existence").

Let me know if you'd like to practice with other sentences!