Ps: um = male indefinite article. Uma = female indefinite article.
About this, when learning portuguese this is one of the hardest parts. Not always it'll work like:
"A woman" - woman is female so
a should translates to
uma.
In this case,
a is in fact translated to
uma but not because a woman (a real woman) is female, sometimes it works different.
For example:
"A house" or even
"a city" as victor already used - how can you possibly tell if a house or a city is male or female (grammatically)? Common sense would tell you to go for
um as proper translation but it's wrong. The correct translation is
uma casa and
uma cidade, not because we see them as female figures in any mean, but simply because it is like that in our grammar.
The best way to fix that in your mind is practicing by hearing/reading/talking, but there are some tips and cheats (though they wont work every time).
I'll drop this link (in portuguese) that victor provided me and ended up being very useful:
Portuguese for foreigners - Nouns
Basically it explain how
every noun has a gender (also a number and
degree? Still not sure how to translate it) and not only the article but the whole sentence structure can change depending on that. Here's a small part of the text:
Primeiramente aprenderemos as flexões dos substantivos:
Gênero - Todo substantivo possui um gênero, que pode ser masculino ou feminino. Geralmente substantivos terminados em -a são femininos e substantivos terminados em -o, masculinos. Exemplo:- Braço (masculino)
- Livro (masculino)
- Calça (feminino)
- Bolsa (feminino)
First of all we're going to learn nouns flexions:
Gender - Every noun has a gender, that can be male or female. Usually nouns ending in
a are female and nouns ending in
o are male. For example:
- Braço (male)
- Livro (male)
- Calça (female)
- Bolsa (female)
in name of curiosity: Braço = Arm/Livro = Book/Calça = Pants/ Bolsa = Bag
though some of these can change depending on context
Summing up, most of the time seeing if the noun ends in
o or
a makes a lot of difference to determine if it is male or female.
Any questions just ask me or victor