"His birthday is in December."
Translation:Jego urodziny są w grudniu.
I was looking for jest, but i didnt see it. I thought sa was plural. Is this a bug?
I think I may have one
When you say "my birthday is in may" you are basically saying that all of your birthdays are in may
Think of it this way
that may be the way to remember it.
But that is not how it works in Polish. Like narodziny (bith) are rather once in a liftme thing, and zaręczyny (engagement) are rather singular thing