Sentence:  [G]raphic novelists must think "inside the box" in some significant ways. Like comic books, each page of a graphic novel usually displays from one to nine outlined <WSD>boxes</WSD> with pictures and words that tell a story. Another tradition places the descriptions of events or scenes in smaller rectangles set within panels. These rectangles are called narrative <WSD>boxes</WSD>. ... Use narrative <WSD>boxes</WSD> with words such as "Far away" or "Meanwhile" to tell readers when you are moving the action somewhere else. 
Meaning of the word marked with <WSD> tags:  A rectangle: an oblong or a square.