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Choosing Preview Page Display Mode
Documents can be displayed in four different modes.
Choose View > 1-Up Display Mode to display one page at a time. This setting is the default.
Choose View > 2-Up Display Mode to display two document pages simultaneously, with the recto page always displayed in the right-hand position. The first page of a document is always displayed in the right-hand window.
Choose View > Continuous Display Mode to scroll the document pages one after the other.
Choose View > Options > Extended Pages to display all text formatted to appear on a page, whether or not it actually will appear on that page. This mode is primarily intended for use by page layout designers.
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Extended Pages mode runs more slowly than the other preview modes, so it is not recommended for regular use.