Olá. Welcome to this short lesson on these prepositions: a versus em.

So, in this context, they are prepositions of time, namely when we refer to days of the week, and we talk about routine events and one-off events. So as we’ll see, a is associated to routine events, those events that will usually repeat on a regular basis, whereas em is associated to one-off events. So, for example, here we have a rotina, evento rotina.

This sentence: “Ao sábado costumo ir nadar.” On Saturdays,

I usually go swimming.

So you see, this is a routine. Notice that we have the contracted form, so sábado, masculino singular, masculine singular, and therefore the contraction between a, preposição, and the article o. O sábado, ao sábado costumo ir nadar. Again, on Saturdays, I usually go swimming.

À segunda tenho ensaio coral.

On Mondays, I normally have choir rehearsal. Again, contracted form, a plus the article a. Segunda, segunda-feira, singular feminino, a segunda-feira, and therefore, à segunda-feira tenho ensaio coral. I have choir practice on Mondays. Now,

I use the singular form of these days, sábado, segunda, but it’s common also to use the plural form,

just like we say in English, on Saturdays, on Mondays, we can say in Portuguese, aos sábados, às segundas, and there’s no difference. It’s the same thing. It’s up to you. Ao sábado, aos sábados,

à segunda, às segundas. Let’s now see evento pontual, em, so this is the one-off event.

Same examples, but now we have: No sábado vou nadar. So this is this Saturday

I will swim.

Na segunda-feira, na segunda tenho ensaio coral. On Monday, I have a rehearsal, I will rehearse with the choir. So again, em, evento pontual, one-off events, and contraction with the article. O sábado, a segunda, no sábado, na segunda. Now in English, we often say, this Saturday, this Monday, and we can also do the same thing in Portuguese with the demonstratives: este, esta. Este sábado vou nadar. Esta segunda tenho ensaio coral. It’s basically the same thing. No sábado vou nadar. Este sábado vou nadar. Okay? Same meaning. This is it. A, routines, em, one-off events. Até a próxima.