"You are a woman and I am a man."
Translation:Você é uma mulher e eu sou um homem.
you can only do that with eu and nos (my keyboard doesn't have accents sorry) because sou and sonos don't go with another pronoun whereas é could be você and ele/ela unless the subject is already known, already mentioned i' m not native so i don't know about informal uses of the languages that's the best i can give you ^^'
"Ser" and "Estar" are both translated into "to be" in English, but they have a difference in meaning that cannot easily be shown in English. "ser" is used when referring to defining characteristics or permanent states. For non-defining characteristics, or temporary states, you use the word "estar" See http://www.learningportuguese.co.uk/language/irregular-verbs.html for more details.