What is the simple subject of ,Many stories about the first Valentine's Day exist?

The complete subject is, Many stories about the first Valentine's day. The simple subject is stories.

Right.

What do Many stories about the first valentine's Day exist

To identify the simple subject of a sentence, you need to find the main noun or noun phrase that the sentence is talking about. Here's how you can determine the simple subject in the given sentence:

1. Read and understand the sentence: "Many stories about the first Valentine's Day exist."

2. Identify the main verb: The main verb in this sentence is "exist."

3. Ask yourself the question "What or who exists?" In this case, the answer is "Many stories about the first Valentine's Day."

4. Focus on the noun phrase that directly follows the verb: "Many stories about the first Valentine's Day."

5. The simple subject of the sentence is "stories." The word "stories" is the main noun that the sentence is discussing.

So, in the sentence "Many stories about the first Valentine's Day exist," the simple subject is "stories."

The verb is "exist." The simple subject is the word that tells what exists.

I'll be glad to check your answer.

Note the prepositional phrase. Subjects and verbs are never in prepositional phrases.