Dans un magasin vs. au magasin?

Question

Dans cette phrase, "Alors, nous sommes allées dans un magasin...", pourquoi est-ce qu'on écrit "dans un magasin" et pas "au magasin"?

Accepted Answer

Hi T, 
It is the difference between -
... so we went to a shop = ... alors, nous sommes allées dans un magasin
and 
... so we went to the shop = ... alors, nous sommes allées au magasin
Hope this helps!

Answer

I don't know about all of the text that you are querying, but this is a matter of "specific" versus "non specific"

Un magasin -- non specific. Au magasin -- specific. I imagine that the shop or store was previously referred to therefore au magasin (at the store / shop) as opposed to a store in a general sense.

Hope this helps.

Alan (Jim)

Answer

Merci Jim et Cécile!