Two or more things are overlapping if one of them covers up some part of the other so you can't see the one behind. The two leaves in the picture are overlapping.
Some things are together if they are grouped somehow, either because they are near each other or the are doing something related. The four teenagers in the photo are going shopping together. Often business associates will work together on the same project.
Uis forUnderneath
Underneath is a more interesting way of saying under. The cat in the picture is underneath a dishwasher.
Something is vertical if it goes straight up and down. The lines in the picture are vertical. The opposite of vertical is horizontal.








