Many stories about the first Valentine's Day exist.. What is the simple subject?
The first thing to do is to put parentheses around the prepositional phrases.
Many stories (about the first Valentine's Day) exist.
The subject, verb, and complements can never be in a prepositional phrase.
What does that leave for the simple subject?
Some shy people send unsigned cards
To find the simple subject in a sentence, you need to identify the main noun or pronoun that the sentence is primarily about. In the given sentence, "Many stories about the first Valentine's Day exist," the simple subject is "stories." This is because the sentence revolves around the existence of stories.
To determine this, you can break down the sentence as follows:
Subject: Many stories about the first Valentine's Day
Verb: exist
In this case, "stories" is the main noun that the sentence focuses on, making it the simple subject.