They say the people could fly. Say that long ago in Africa, some of the people knew magic. And they would walk up on the air like climbin up on a gate. And they flew like blackbirds over the fields. Black, shiny wings flappin against the blue up there.

–“The People Could Fly,”
Virginia Hamilton

How does the author help the reader understand what is meant by the word flappin?

by defining the word in the glossary at the end
by using the word many times in the story
by using a comparison in another sentence
by having the people use a magic language

by using a comparison in another sentence

In the sentence preceding the mention of "flappin," the author describes the people flying like blackbirds over the fields. This comparison helps the reader understand that "flappin" refers to the movement of the people's wings as they fly through the air.