In portuguese it is possible to put a definitive article in front of proper names. The definitive article is normaly used to identify a determined element of a group of similar elements.
1) The man crosses the street. <=> 2) A man crosses the street.
In the case 1) a specific man crosses the street. This sentence is used if we talk about a man well known. In 2) just any man crosses the street. 1) is actually very similar to "This man crosses the street".
In relationship to proper names it is obviously not used in this sense and actually it doesn't have any semantic value. A sentence like "The John crosses the street" doesn't make sense. John is already well defined and the definite article is superfluous.
We can read in some portuguese grammar books that in front of proper names the definite article is compulsory.
Onde
está
a
Teresa?
Where
is
the
Teresa?
Where is Teresa?
O
Rui
vai
chegar
amanhã.
The
Rui
goes
to arrive
tomorrow.*
Rui will arrive tomorrow.
* with ir + infinitivo we can form the futur in Portuguese. As already said very often, we use sometimes grammar structures that has not been introduced before. We will discuss the future later.
However the already mentioned Sérgio Rodrigues, see 4.1.2.1, doesn't agree. (And as professional, brasilian linguist we suppose that he knows what he is talking about.)
A língua portuguesa, em ambas as variedades, português europeu (PE) e português brasileiro (PB), admite o uso facultativo de artigo diante de nomes de pessoas ou antrop{#ó|ô}nimos. Assim, o uso ou não é função da região. No Sudeste do Brasil, em geral, bem como em Portugal, usa-se; já no Nordeste do Brasil, não é comum. Entretanto, os moradores do Rio de Janeiro que atravessarem a ponte e forem para Niterói, cidade vizinha, {#vão-se|vão se}** deparar com um grande contingente de falantes omitindo, como os baianos, o artigo diante de nome de pessoa. Em conseq{#u|ü}ência disso, as preposições em posição anterior ao antrop{#ó|ô}nimo também serão usadas em conformidade com o uso ou não do artigo.*
In European as well as in Brasilian Portuguese the use of the definitive article before proper names is optional. Whether it is used in this context or not despends on the region. In general it is used in the south-est of Brasil and in Portugal, but already in the north-east of Brasil it is not used any more. The inhabitants of Rio de Janeiro that cross the bridge to Niterói, a near by city, will encounter a lot of speakers who, as the inhabitants of Bahia, don't use a definitive article in front of proper names.Therefore the prepositions before proper names are used as well in compliance with the use of the article.
(With the last sentence he refers to the fusion of prepositions. O livro de Maria <=> O livro da Maria. If an article is used in general, it is "O livro da Maria" otherwise "O livro de Maria.)
*The spelling antrop{#ó|ô}nimos and {#vão-se|vão se} is the way it is written in the original text. This indicates that antroponimos can be pronounced with a closed o, antropônimos, as well as with an open o, antropónimos. In the Dicionário Online de Português it is written with a closed o. This seems to be the European version.
**In European Portuguese personal pronouns are added after the verb with a hyphen, in Brasilian Portuguese the hyphen can be omitted, therefore 'vão-se deparar' as well as 'vão se deparar' (one will encounter) are possible. The discussion concerning this issue is very similar to discussions we find in other languages, see Colocação pronominal entre verbos. There is always a group that believes that on variation is nicer than the other and vice versa.
However in front of continents, countries, cities, rivers and mountains there is a definitive article. (In the the following sentences we have a fusion of preposition + article, see 4.1.1. It seems that rivers in Portugues are always masculine. Even if the river is feminine in the original language and even if it finishs on a as the Portuguese name of the German river Mosel it is masculine in Portugues (die Mosel = o Mosella). (By the way: We have in this case a definitive article in any language, in English as well, although the definitive article is completely superfluous and doesn't have any semantic value. We don't lose any information if we say "River Thames flows through southern England" instead of "The River Thames flows through southern England". However there is no article in English before countries.)
O
Reno
nasce
nos
Alpes,
no
leste
da
Suíça.
The
Rhin
originates
in the
Alpes
in the
east
of the
Switzerland
The Rhin originate in the Alpes in the east of Switzerland.
O
rio
Guadalquivir
está
situado
no
sul
da
península
Ibérica.
El
river
Guadalquivir
is
located
in the
south
of the
peninsula
iberian.
The Guadalquivir is located in the south of the Iberian Peninsula.
O
Ganges
localiza-se
no
norte
da
Índia
e
possui
2.500 km
de
extensão.
The
Ganges
located itself
in the
north
of the
India
and
has
2500 km
of
length.
The Ganges is located at the north of India and is 2500 km long.
O
Mosela
é
um
rio
do
nordeste
da
França,
do
Luxemburgo
e
do
oeste
da
Alemanha.
The
Moselle
is
a
river
from the
nord-east
of the
France,
of the
Luxembourg
and
of the
west
of the
Germany.
The Moselle is a river located in the north-east of France and Luxembourg and in the west of Germany.
Before mountains there is a definitive article as well. If we look at this list, Lista de montes, we see that they are all masculine. The only exception are the mountains that have compound names if one of these components is feminine, for instance a Serra Nevada, a Cordilheira Bética etc..
O
Monte Branco
é
a
mais
alta
montanha
dos
Alpes
The
Mont Blanc
is
the
more
high
mountain
of the
Alpes.
The Mont Blanc is the highest mountain in the Alpes.
O
Jungfrau
foi
escalado
até
ao
topo
pela
primeira
vez
em
1811.
The
Jungfrau
was
ascended
until
to the
peak
for the
first
time
in
1811.
The peak of the Jungfrau was ascended for the first time in 1811.
O
Teide
é
um
vulcão
situado
na
ilha
de Tenerife.
The
Teide
is
a
vulcano
located
in the
island
of Tenerife.
The Teide is a volcano located on the island Tenerife.
Concerning the continents there are no stable rules. Sometimes an article is needed and sometimes not and the article can be masculine or feminine.A complete list of all countries with the respective articles you can find here: Países.
In case that the name of a country is part of the title of an article, there is no definitive article. All the articles about countries in Wikipedia are without article.
Espanha
é
um
país
situado
na
península
Ibérica.
Spain
is
a
country
located
in the
peninsula
iberian.
Spain is a counry located on the iberian peninsula.
A
Noruega
é
um
país
europeu
localizado
na
península
Escandinava.
The
Norway
is
a
country
european
locatedd
on the
peninsula
scandinavian.
Norway it a european country located on the scandinavian peninsula.
