Viewing

Individual Fields

You can view a field code by clicking inside it and pressing (Shift + F9).
Or you can right click on the field and select Toggle Field Code.
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All Fields

The actual fields are rarely displayed in a document although you can display them by selecting (Tools > Options)(View tab, Field Codes).
To view all the field codes in the document press (Ctrl + A) followed by (Shift + F9).

Viewing field codes and field results

It is possible to display both the field code and the field results at the same time.
Open a second window (Window > New Window).
In one window choose (Tools > Options)(View tab, Field Codes)
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