They are especially important in Portuguese because the conjugation of verbs changes depending on the subject.
In English, subject pronouns are words such as "you", "we" and "it".
Portuguese, however, is slightly more complicated because of its use of formality and the wide regional differences. For example tu is the informal word for "you", but is used primarily in Portugal. In Brazil, você is used much more frequently as the informal "you", despite it being the formal "you" in Portugal.
To address someone formally in Brazil, o senhor (masculine) or a senhora (feminine) are used. In Portugal these would seem overly formal as they translate as "sir" or "madam".
Because in Brazil both the formal and informal second-person pronouns take the traditionally third-person verb conjugation, you'll find that they drop subject pronouns much less frequently than in Portugal or as in Spanish.
Simplifying it somewhat though, Portuguese has no subject pronoun for "it", which is generally implied in the sentence.
you informal Portugal
you formal Portugal you informal Brazil
you masculine formal Brazil
you feminine formal Brazil
Hello, I’m Guilherme, one of the Portuguese Ambassadors and today I’m going to answer the question: What’s the difference between “tu” and “você”? The quick answer is: they both mean “you”. But, when you’re using “tu”, you have to use the second conjugation, the second person and when you’re using “você”, it’s the third person conjugation. The main reason for this, it’s because in the past “você” was kind of like a title, so it’s kind of like saying “Your Highness” or “Your Honour”. But, you’re never going to say “Your Highness are right or wrong”, you’re going to say “Your Highness is right or wrong”. It’s the third person. So it’s the same idea, when you use “você” it’s the third person. So for example, if we’re using the verb “to eat”, “comer”, if you’re using “tu”, you’re going to say “tu comes”, but if you’re using “você”, you’re going to say “você come”, which is the same as “he” or “she” or “it”. “Ele come”, “ela come”, “você come”. You’re probably going to hear a lot more “tus” in the south of Brazil and the north of Brazil. And kind of like in the middle, a lot more “você”, Rio de Janeiro, São Paulo, Minas Gerais. And when it comes to Portuguese from Portugal, the main difference is that “você” is formal and “tu” is informal. So, in a formal setting, you’re going to say “você”, “você”, “você” and in a informal setting, “tu”. And, I’d say this is probably, yeah, the main difference.