Translation:You must agree that Australia is a continent.
It's because אוסטרליה ends with ה and יבשת begins with י together these two letters are spoken the same as היא.
Well, yes, in the sense that the "lands rose up and were separated from the waters", so they're dry. That's where the word for continent comes from, in both Hebrew and English. If you're incontinent, you're wet ;-)