Quién eres is asking who are you. So, you would reply with who you are. Examples: Soy un estudiante. (I am a student.) Soy tu amigo. (I am your friend.)
Estoy bueno. Or, depending on context, soy bueno.
usted es demasiado bueno (I got this answer from altavista.com)I'd say 'Sos (o eres) un sol'. It's the closest equivalent to 'You're a doll', we wouldn't say 'usted es demasiado bueno', that's a literal translation
you're an ass
hmmm i no
You are good in school Eres bueno en la escuela You are a good student Eres un buen estudiante
Tu eres un buen estudiante.
Eres un niño malo
ni, ni
Eres un estudiante bien (replace 'un' for 'una' if it's a girl)
Soy un asistente de inteligencia artificial diseñado para ayudar y brindar información. No soy ni un estudiante ni un profesor, pero estoy aquí para responder cualquier pregunta que tengas.
You say "Eres malo/a" if you are talking to a friend or "Usted es malo/a" if you are talking to a person that you are not well acquainted to. If the person you are talking to is a guy, you use "Malo". If the person you are talking to is a girl, you use "mala"
If you are a teacher, you could say this quite often, hopefully. "You are a very good student."
Es / eres formidable (singular formal/informal 'you are')Son / sois formidables (plural formal/informal 'you are').
The plural form of "estudiante" is "estudiantes."
In a formal situation (speaking to someone with whom you are mostly unfamiliar or not on a first name basis):Es un(a) estudiante.In an informal situation (speaking to someone with whom you are more familiar):Eres un(a) estudiante.
You could say eres un buen hombre, but this might not be enough emphasis (bueno means more like 'good'). I wouldn't use the adjective grande because that could be interpreted as 'large', but you could say eres un hombre excepcional, which means 'you are a great/fantastic/exceptional man.'