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    Post Closed as "off-topic" by πάντα ῥεῖ, Glorfindel, peterh, Robert, Björn Friedrich
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What is the difference between ein Monat, einen Monat, and einem Monat?

I am confused as to when to use each of the three phrases from the title, especially the “einem Monat”

Would saying “in less than one month” be “Weniger als ein Monat noch“ ?

Thank you!