QUICK ANSWER
"You are" is a form of "you are", a phrase which is often translated as "eres". "Yes" is an interjection which is often translated as "sí". Learn more about the difference between "you are" and "yes" below.
you are(
yu
ar
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. eres (informal) (singular)
A word or phrase used to refer to the second person informal “tú” by their conjugation or implied context (e.g., How are you?).
A word or phrase that is singular (e.g., el gato).
You are my best friend.Eres mi mejor amigo.
b. es (formal) (singular)
A word or phrase used to refer to the second person formal “usted” by their conjugation or implied context (e.g., usted).
A word or phrase that is singular (e.g., el gato).
Thank you, sir. You are very generous.Gracias, señor. Es muy generoso.
a. estás (informal) (singular)
A word or phrase used to refer to the second person informal “tú” by their conjugation or implied context (e.g., How are you?).
A word or phrase that is singular (e.g., el gato).
I know you are mad, but you need to calm down.Sé que estás enojado pero tienes que tranquilizarte.
b. está (formal) (singular)
A word or phrase used to refer to the second person formal “usted” by their conjugation or implied context (e.g., usted).
A word or phrase that is singular (e.g., el gato).
You are on 30th Ave. Broadway is that way.Está en la avenida 30. Broadway queda por allá.
yes(
yehs
)An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
An interjection is a short utterance that expresses emotion, hesitation, or protest (e.g., Wow!).
A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).