This is not the preview but while working
you may want to concentrate on particular object. You can zoom it
using zoom tool but there is a shortcut.
1. Open Corel Draw.
2. Select Ellipse tool and draw the circle within
the page area and fill it with any color. Select Rectangle Tool
and draw rectangle, fill it with some other color. You can draw
few more objects and fill the color. Place them near each other
on the page.
3. Select circle.

4. Press Shift + F2
5. Only circle which is selected is zoom in the window
to its maximum extend and you can work on it without the disturbance
of any other object.

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