Click Chained Dimensions
in the Annotations toolbar (Dimensions sub-toolbar).
Click a first point on the view.
Click a second point on the view.
You just created a first dimension within the chained
dimension system.
Click a third point on the view.
You now created a second chained dimension in the system.
You can create as many chained dimensions as desired.
Note:
If you move one dimension line as you create
a chained dimension, all the lines will move accordingly. In the same
way, clicking on one dimension line highlights all the lines showing
the whole system is selected.
Click in the free space to end the chained dimension
system creation.