What is the effect of Dunbar's word choice on
the tone of the poem?
He creates a tone of longing by
describing things that he feels are
out of reach to him.
He suggests a tone of defiance by
describing his emotions when faced
with challenges.
He sets a hopeful tone by
contrasting the negative with the
positive.

He develops a dejected tone by
comparing his difficult experience
with that of another.

(you didn't attach a copy of the poem, but i'm answering as best as i can)

since a simile compares two unlike things using like or as, it kind of gives an item the ability to do something it can't.

example: "the player was like a tiger on the field"

in this sentence, the simile conveys the idea that the player was fast and strong, like a tiger.

in the secret life of walter mitty, the main character leads a dull life, or so he thinks.in all his daydreams he plays the role of some hero or a man who is unbelievably resourceful.whether a pilot, a surgeon   or even a criminal, he is better, so much better than all the rest of the characters in his delusions.he comes up with ideas nobody else could have conceived .when he comes back to reality, whatever he has to deal with seems silly, boring without any motivation to deliver.

in a sound of thunder a hunter,eckles, wants to use a time machine to go back in time to catch a tyrannosaurus rex. by then, 2055 elections were go held and a   new hitler was beaten by a far better candidate, keith.once he and other men have traveled,   he gets cold feet. he in   some way has known   this is not a good idea.he hears this sound , too strong for him to put up with . hopeless, he abandons the project making a mistake - another one as the first is to travel in time-that causes a butterfly effect when he comes back. in the end , changes reality for worse; the anti human anti christ deutscher,   is the president.