"I'll become an architect at this agency."

Translation: Je deviendrai architecte dans cette agence.

[OldMansChild]

used "à" and was marked wrong. Duolingo never explained why, so is this same as the "au restaurant/dans ce restaurant" stuff? (duolingo never accepted "à ce" in my experience).

[GraemeSarg]

I don't think it's just Duo. The French avoid saying "à ce(tte)" (unless there is no viable alternative).

[Shelley54877]

Elsewhere, Duo required the article when the sense was more specific than a general career field. Here, "at this agency" seemed to require the article. Please clarify.

[GraemeSarg]

I think you may be confusing the dropping of the article for a person in a profession with the place of work, which does not drop its article (unless the appropriate preposition is "en").

[VivianIjeo]

Pourquoi cette agence. Je pense que cet agence parce que ce mot commençe avec le voyel "a"

[Atervanda]

On emploie « cet » pour les noms masculins qui commencent avec une voyelle ou un h muet. Pour les noms féminins, on emploie toujours « cette ».