You can choose a template for the pattern from the combo box and edit it here. The string %s in the template is replaced by the pattern input field, resulting in the regular expression to search for.
Jo kinne in út it kombinaasjefjild in sjabloan kieze foar in patroan en hjir bewurkje. De string% s yn de sjabloan is ferfongen troch it patroan ynfier fjild, wat as resultaat hat in algemiene útdrukking om nei te sykjen.