You have "minimized" (hidden) the Ribbon. There are several ways to get it
back, but IMO the easiest is just to double-click any one of the tabs.

Signature
Suzanne S. Barnhill
Microsoft MVP (Word)
Words into Type
Fairhope, Alabama USA
http://word.mvps.org
> Suddenly when I'm working on a document I have to click on "home" or
> "view"
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> disappear and I have to click "home" (or whatever) each time to see them.
> How did this happen and how do I fix it???