Translation:There are very many chairs in the atrium.
Cultural notes: Atria are still a very common feature in buildings in Spain. Even when space is limited, for example in an apartment building, they will find one square meter of open-air space that reaches from ground floor to the roof. Here are some notes regarding atria, from the Roman tradition to present:
At some point I am sure there will be more lessons. This is the most recent post I have seen posted from contributors about new content: https://forum.duolingo.com/comment/38030583
Stories are a lot less likely (at least for the foreseeable furture), not many courses have stories (only five learning from English by the looks of it).