Check box, combo box
Determines whether a user can use the Tab key to set the focus to a control.
[form.]control.TabStop[ = boolean ]
The TabStop property settings are:
True (Default) Designates the control as a tab stop.
False Bypasses the control when the user is tabbing, although the control still holds its place in the actual tab order, as determined by the TabIndex property.
This property allows you to add or remove a control from the tab order on a form. For example, instead of moving through each button in an option button group, you can treat the whole group as one tab location. To do this, set TabStop to True for the first option button in the group and set TabStop to False for the other option buttons in the group.
Specifying Access Keys
Chapter 3, "Creating and Using Controls"