Are you sure?

A bheil thu cinnteach às?

We use à/às (out of) when we say we are cinnteach (certain or sure).

We form riochdairean roimhearach (prepositional pronouns) with à as follows:

à + miasamout of me
à + thuasadout of you (singular)
à + eàsout of him/it
à + iaisteout of her/it
à + sinnasainnout of us
à + sibhasaibhout of you (polite/plural)
à + iadastaout of them
A bheil thu cinnteach às na dh'ionnsaich thu?
Are you sure of what you have learned?
Chan eil mise idir cinnteach asta.
I am not at all certain of them.
Chan eil mi cinnteach às a sin.
I am not certain of that.
Tha mi cinnteach às.
I am certain of it.