fur's

I can't put the umlaut over the "u" but in lesson 2.4 Matthias tells Sandra she owes forty euros for fuel, and two euros for oil. Why does fur have an apostrophe and "s" when he tells what she owes for oil?

Hallo! the reason Matthias says "für's" is because the article for "oil" is omitted. Matthias could have said: Für das Öl. The abbreviated version is "für's Öl". In spoken German you would use the shorter version. I hope that helps. Paul