This is the 10832nd most frequent German word.
sie
"Sie" can mean "she," "they," or the formal "you," depending on context.
The pronoun 'sie' functions here as a singular feminine subject pronoun, referring to the third-person singular 'she'.
Sie liest ein Buch.
She is reading a book.
In this usage, 'sie' acts as a singular feminine object pronoun in the accusative case, referring to 'her'.
Ich sehe sie im Park.
I see her in the park.
Here, 'sie' is used as a plural subject pronoun, referring to 'they'.