This image shows the Expression Editor dialog. The Expression Mode field is displayed at the top of the Editor. You can choose the mode from a drop-down list. The Expression Editor is then divided into these areas: Expression Field, Insert into Expression, Data Object and Operator Chooser, Description, and Errors. The Expression Field contains the text of the expression. You can edit this field directly, or use the Insert Into Expression tool. The Data Object Chooser are tabbed panels that lets you select data objects and operators for your expression. The Description field displays the description of the selected operator. The Errors tab displays any errors in your expression. If errors occur they will display when you validate your expression.