Group or ungroup objects
Group
individual selected objects and then manipulate them as if they
are a single object. For example, after drawing the petals of a
flower as individual objects, group them to select and move the
entire flower as a single object.
You can edit groups without ungrouping them. You can select an
individual object in a group for editing without ungrouping the
objects. You can also ungroup the objects at any time.
Select Modify > Group or Modify > Ungroup.
Select objects within groups
To
work with individual objects within a group, either ungroup the
objects or use the Subselection tool 
to
select individual objects while leaving the group intact.
Modifying the attributes of a subselected object changes only
the subselected object. Moving a subselected object to another layer
removes the object from the group.
Subselecting an object within a group
Select an object that is part of a group
Select the Subselection tool and click the object
or drag a selection area around it. To add objects to or remove
them from the selection, hold down Shift as you click or drag.
Select the group that contains a subselected object
Do one of the following:
Select all objects within a selected group
Do one of the following:
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