This is the 124th most frequent Czech word.
ty
"You" (singular, informal).
In this sentence, 'ty' is a pronoun in the nominative case referring to the second person singular, used to directly address someone.
Ty jsi moje kamarádka.
You are my friend.
Here, 'ty' is a demonstrative pronoun in the accusative case, referring to specific objects (the flowers) observed by the speaker.
Vidím ty květiny na stole.
I see those flowers on the table.
In this example, 'ty' is again a pronoun in the nominative case but emphasizes the subject (the person being addressed) to underline the action described.