What contains pronouns which are used as objects in a sentence?

This is a bit of a tricky question! It's not a specific thing that "contains" object pronouns, but rather sentences themselves that use object pronouns.

Here's why:

* Pronouns are words that stand in for nouns (e.g., he, she, it, them, us).

* Object pronouns are the specific types of pronouns used when the pronoun is the *receiver* of the action in a sentence.

For example:

* "He" is a pronoun, but in the sentence "The dog chased him", "him" is the object pronoun because it's the one being chased.

So, to answer your question directly, sentences contain object pronouns when they're used to represent the receiver of an action.

Let me know if you'd like more examples or have other questions!