I'd like to offer some advice if I may
Humble, if you going to specifiy details, i.e. the location, then you would write:
Maude is a teacher. She works at a school (in Rothermond Street/New Hampshire etc etc)
You see, by using 'a', the marker will assume there is additional information to follow, which I'm assuming there's not in this instance
So in your case:
Maude is a teacher. She works at school.
Works fine
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