The Composition tab consists of three subgroups: Movement, Remove, and Marking.
The Movement group contains buttons to move pages in the document. If you move a page up or down, it will change its number in the document.
The Move Up button moves the page up in the page list. It will decrease the number of the page in the document.
The Move Down button moves the page down in the page list, which increases the number of the page in the document.
The Move to Top button moves the page to the very beginning of the document, making it the first page in the document.
The Move to Bottom button moves the page to the very end of the document, making it the last page in the document.
The Move to Position button allows you to move the page to an arbitrary position.
When a dialog box appears, enter a new number for the page in the document, and then click the OK button.
The Remove group contains a button for removing one or more pages from the document.
The Remove Page button removes the current page. If you have marked several pages, all of them will be removed.
Alternatively, use this hotkey: Del.
Before removing pages, the application will ask you to confirm the operation.
The Marking group contains buttons to mark pages in the document. You can apply group operations to the marked pages (read more in the Group operations section).
The Mark All button marks all pages in the document.
Alternatively, use this hotkey: Ctrl+A.
The Unmark All button unmarks all pages in the document.