in which sentence is barn used as the object of a preposition

To identify a sentence in which "barn" is used as the object of a preposition, we need to look for a sentence that includes a preposition followed by the word "barn". A preposition is a word that shows the relationship of a noun or pronoun to another word in the sentence.

Let's consider a few examples:
1. The horse is running in the barn.
2. Jack is playing with the barn.
3. She walked past the barn.

Now, let's analyze each sentence to determine which one uses "barn" as the object of a preposition:

1. In the sentence "The horse is running in the barn," the preposition "in" is followed by the noun "barn," making "barn" the object of the preposition.

2. In the sentence "Jack is playing with the barn," the word "with" can act as a preposition, but in this context, "barn" refers to a toy and not a physical structure. Therefore, it is not used as the object of a preposition.

3. In the sentence "She walked past the barn," the preposition "past" is followed by the noun "barn," making "barn" the object of the preposition.

Therefore, the sentence that uses "barn" as the object of a preposition is: "The horse is running in the barn."