2) Line Direction

Line can show direction in many ways.
For instance the photo below shows a line that draws your eyes towards the background by making your eyes follow it.

The photo bellow shows an implied line that makes you look for what it is that the gestured character is  picking up.

"Ooo used chewing gum!"

Psychic lines are lines that show direction by using something as small as the direction that a character is looking or pointing. Such as in this Caravagio below.

"Do it. You won't do it."