The easiest way that comes to mind currently is to remove the critical faces, add some loop cuts, then create faces.
So for the second one, you would remove the critical face, make a double loop cut with Ctrl R then 2 then extrude the small edge in the middle, and finally select the edge pairs to Fill them with F.
The same applies to the third and fourth with some changes. For the first one: Remove the upper two critical faces, add the loop cuts, fill the proper edge pairs, move the center vertex down.
