Since – ‘Como’ or ‘Desde’ in Portuguese?
Paul Melo e Castro, University of Leeds
p.m.castro@leeds.ac.uk

In English ‘since’ can be a preposition (a word joining an object to a verb), conjunction (a word joining two clauses) or adverb (a word qualifying a verb) indicating time or a conjunction indicating the reason linking clauses.
For the first, temporal meaning, Portuguese uses ‘desde’ (preposition), ‘desde que’  (conjunction) or ‘desde então’ (for adverb)
For the second meaning (where ‘since’ means ‘because’), Portuguese uses ‘como’ (where ‘porque’ is not more natural).
Let’s look at some examples:
Since (time)
I have studied Portuguese since 2010
Estudo português desde 2010 (preposition indicating time, note tense use)
I read The Maias by Eça de Queiroz two years ago but I haven’t picked it up since.
Li Os Maias de Eça de Queiroz há dois anos mas não voltei a pegar no livro desde então (note that in Portuguese ‘desde’ alone cannot be an adverb; it must be combined with the adverb ‘então’).
Since she met Jimmy Saville her life hasn’t been the same.
Desde que conheceu Jimmy Saville, a vida dela não é a mesma (note that in Portuguese ‘que’ is needed to connect ‘desde’ to a verb and that present tense functions as past continuous)
I haven’t seen that cartoon since I was a child
Não vejo aquele desenho animado desde que era criança (note that in Portuguese there is a tendency not to avoid ‘desde’ as a conjunction and use it as a preposition – não vejo aquele desenho animado desde criança or desde criança que não vejo aquele desenho animado)
Since (Reason)
Since you’ve already studied Portuguese, you don’t need to revise basic verb conjugations. (Conjunction indicating reason)
Como já estudaste português, excusas de rever as conjugações básicas dos tempos verbais.

Translate the following sentences:
1)	Since I was a child, I wasn’t allowed to watch the horror film.
2)	Since you started learning to play the drums, I don’t sleep at night.
3)	I have been studying the difference between ‘desde’ and ‘como’ since 8 o’clock this morning and I still don’t get it.
4)	I had to do the shopping since he didn’t have any money.
5)	I have had to do the shopping since he lost his job.
6)	He moved to East Timor in 2013 and I haven’t seen him since.
7)	Since he had an interest in international development and deepwater diving, he decided to move to East Timor.
8)	I have been interested in diving since I was a child.
9)	I took the day off and went diving since it was my birthday.

Ways to distinguish between ‘since’ (preposition, conjunction adverb of time) and ‘since’ (conjunction of cause)
If you can add ‘ever’ before ‘since’ it translates as ‘desde’
Since he learnt Portuguese, all he does is watch Brazilian films.
Ever since he learnt Portuguese, all he does is watch Brazilian films.
Desde que aprendeu português, ele só vê filmes brasileiros.
If you can interpret ‘since’ for ‘because’ or ‘for that reason’, it translates as ‘como’
Since I understood his language, I was able to follow his instructions.
Because I understood his language, I was able to follow his instructions.
Como compreendia a sua língua, pude seguir as suas instruções

Other meanings of ‘desde’ and ‘como’
Just as ‘since’ has several meanings, so do ‘desde’ and ‘como’
As a preposition, ‘desde’ can indicate space as well as time:
Andámos desde a casa até o cinema
We walked from our house to the cinema
It can also indicate variety:
Naquele cinema passam muitos filmes diferentes, desde filmes de gênero até filmes mudos dos anos 20.
That cinema shows lots of different films, from genre films to silent films from the 1920s.
Desde que is also a conjunction meaning ‘as long as’
Desde que tenhas a certeza…
As long as you’re sure…
‘Como’ can be also mean ‘like’ (preposition) or ‘as’ (conjunction)
He jumped like a frog
Ele saltou como uma rã
I reacted as she did
Eu reagi como ela (agiu – note that Portuguese tends to omit a second verb, as it is redundant)