The Copy Formatting feature provides the ability to easily copy text formatting from one place in the document and apply it to another.
The Copy Formatting icon looks like a paint brush and can be found in the main document toolbar:
To copy styles, place your cursor inside the text (or select a styled document fragment) and press the button or use the Ctrl+Shift+C keyboard shortcut. Then place the cursor inside some word or select a part of the text to apply formatting to it. The copied formatting can also be applied by using the Ctrl+Shift+V keyboard shortcut.
For more please visit CK Editor 'how to' page here: