There are just two keywords in the modal category:
and they must be used immediately before the first mention of any modal node,
i.e. any node of type
supp. They must not be used with
subsequent mentions of the same node.
Let I. Then A.
Suppose S. Then B.
So far in this tutorial, we have only seen ways of creating deduction arrows. In the next section you will learn how to create flow arrows.