Prepositions before 'que' (de que, em que)

Prepositions Before "Que"

In English, we usually drop prepositions before the conjunction "that" (e.g., "I remember that...", not "I remember of that..."). In European Portuguese, if a verb, adjective, or noun phrase naturally requires a preposition, it keeps it before the conjunction que.

Let's look at verbs that require de, such as certificar-se de (to make sure of) and lembrar-se de (to remember). When followed by que, the de stays right where it is:

Before entering an unexplored building, I make sure that there is no danger.
Antes de entrar num prédio inexplorado, certifico-me de que não há perigo.
I remember that the respirator saved me when the rubble fell.
Lembro-me de que o respirador me salvou quando os escombros caíram.

Adjectives and Noun Expressions

Adjectives like ciente (aware) and noun expressions like ter a certeza (to be sure) or ter medo (to be afraid) also retain their de before que:

I am aware that exploring this hospital is illegal.
Estou ciente de que explorar este hospital é ilegal.
The degradation is severe and I am afraid that the wall will collapse.
A degradação é grave e tenho medo de que o muro se desmorone.

Verbs with "Em"

The same principle applies to verbs requiring em, like insistir em (to insist on). When followed by a que clause, it becomes insistir em que:

The guide insists that we use the respirator because of the mold.
O guia insiste em que usemos o respirador por causa do mofo.

Prepositions and the Subjunctive

The conjunction que still triggers the subjunctive if the main verb expresses doubt, emotion, or a demand. The retained preposition does not change this:

I doubt that this unexplored tunnel is free of rubble.
Duvido de que este túnel inexplorado esteja livre de escombros.
I like that your team has prudence in the ruins.
Eu gosto de que a tua equipa tenha prudência nas ruínas.