This can help you.
<span>When the speaker sees bent birch trees, he likes to think that they are bent because boys have been “swinging” them. He knows that they are, in fact, bent by ice storms. Yet he prefers his vision of a boy climbing a tree carefully and then swinging at the tree’s crest to the ground. He used to do this himself and dreams of going back to those days. He likens birch swinging to getting “away from the earth awhile” and then coming back. hope this helps you
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Well, definitely by the words of the fisrt statement, it is clear that Irony and sarcasm is incluencing those words, saying something cruel with a bit of humour. The second case is a tragic resolution as for the last sentence states: i vowed revenge. Which could imply serious damaging
:book