Groups provide an easy way to combine drawing objects that you need to manipulate as a unit. By default, selecting any member of a group selects all the objects in that group, and you can move, copy, rotate, and modify groups just as you can modify individual objects.
Objects can be members of more than one group, and groups themselves can be nested in other groups. Selecting an object that belongs to multiple groups selects all groups to which that object belongs.
If you need to edit objects within a group, turn off group selection or use grips to edit individual objects.
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