Creating a field with a non-rectangular region

Sometimes it is necessary to create fields with non-rectangular regions, as exemplified by the questionnaire:

To create a non-rectangular field region:

Select the tool for creating a field of the required type.
Select a rectangular region where you can add or remove fragments to create a region of the required shape.
Select the tool and make sure that the rectangular region is highlighted.
To add a fragment to the region, press the Shift key (the cursor will appear as a “plus” sign) and highlight a fragment you want to add.
To exclude a fragment from the region, press the Alt key (the cursor will appear as a “minus” sign) and highlight the fragment you want to exclude.

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