I.R.I.S. Readiris 14 for Mac User Guide - Manual (Page 81)

Section 7: Editing the Recognition Zones
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 Click the Layout icon to display the Layout tool.
 Click the Text icon.
 Then draw a text zone that overlaps the two zones to connect
them.
 The two zones are merged into one.
Note that only zones of the same zone type can be connected.
OR
 Close the Layout tool.
 Click a zone to select it. The entire zone is now marked in its
corresponding color and the markers on the borders are
displayed.
 Click one of the markers and expand a side of the zone until it
overlaps with another zone of the same type.
 The two zones are merged into one.