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Fields are invisible most of the time in word. To make them appear, use Alt+F9 to toggle between having them visible and not.
All fields begin at the Fields pop-up box. The easiest way to get there is under the "Insert" tab, then the "Text" section, under "Quick Parts" and then "Field." Click on the "Field Codes" or "Options" buttons to get to the useful features of your field.
If the field you want to insert does not fit in the Field Codes line, return to the document to add additional text. With codes visible (Alt+F9), type in the desired text. Then, right-click on the text and select "Update Field."
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