What does the support of a paragraph do

What is the meaning of the word checking as it is used in this sentence from the second paragraph of the passage?

Which statement is true of the antagonist of a character vs. nature conflict? the antagonist is generally more powerful than the protagonist. the antagonist is a person or personified object. the antagonist and the protagonist have the same values. the antagonist is always difficult to fletermine.

Give example of metaphors and similes