Translation:Mara's mother lacks money. So she cannot buy my interesting book.
And I take it that there was no single tile with "Mara's" on it in the word bank?
That's an unfortunate effect, then! I'd suggest that you report it to Duolingo HQ as a buq: https://support.duolingo.com/hc/en-us/articles/204728264-How-do-I-report-a-bug-