Hello, it was a long time ago. Now I should like to make a ring again with a hole in the middle. It works with Path>Difference if it is only 2 ovals. But if I want to make a ring looks like a road with broken white lines, that is no problem with several scaled ovals with stroke stiles. I smelt them by grouping objects or by path>union. Then I put an oval in the middle and want make Path>Difference. It doesn't work! If I use Object>clip, I have only the middle-oval left, the other disappears.

That's the problem with clip: the shape you use is the part that is displayed, not the part that is cut out. If you use version 0.46, the Composite filter effect can give you what you want by using the "Out" compositing mode. I haven't yet used 0.46, so I can't give a detailed description of how to implement it.

In 0.45, you can get what you want by creating a specially shaped and colored mask that does what you want. Check out the end of my "Holes" guide for the procedure: http://kelan.freeshell.org/inkscape-holes.svgz (Note: You'll need to load the file in Inkscape. Browsers don't render it correctly.)

Basically, you create a clone (or dynamic offset) of the object, fill it with white, and group it with a black object that's the shape of hole you want. Then use that as a mask.

Thank you, kelan. It was not so simple as I beleived, that was simple and sophisticated at the same time.

I have discovered that my question went lost. I would place it into Help with Using Inkscape.