"I work in Shrewsbury."
Translation:Dw i'n gweithio yn Amwythig.
I would like an answer to that as well as I have been marked wrong twice now.
This is explained in the course notes
In short, yn is used for 'in/at' somewhere in particular (Shrewsbury, the office, the pub,...) and mewn is used for 'in/at a' place that is non-specific (a town, a shop, an office):
- Dw i'n gweithio yn y llyfgell leol - I work in the local library
- Dw i'n gweithio mewn llyfrgell leol - I work in a local library