Modal Logic [Girle Syntax]
You are invited to review
Extensive use is going to be made of Trees or Tableaux. A good way in, even before you get started on this material, is to look at the Notes on on Trees, say the first three tutorials. [Those Notes use → for the conditional, we're going to use ⊃ right now]
The text that is essential is
Rod Girle  Modal Logics and Philosophy
All we are going to do is to provide software support, so that you can explore the systems he explains (and do more of his exercises (quickly and correctly)).