Throughout the novel there are circumstances in which Gatsby shows he is modern such as his clothes, his car and even his house. These are all things that are different from other for example Tom who is old fashioned and the opposite of Gatsby.
The prepositional phrase is "on a high shelf" since ON is a preposition.
<span>"Found" by Margaret Peterson Haddix is a fictional story about two 13-year-old boys Jonah and Chip. Jonah knows from the beginning that he is adopted, but Chip is shocked to find out that he is too. Through a series of unexpected events, the boys discover that their pasts extend beyond the normal span of time. Soon they realize that they aren't the only ones who were mysteriously abducted and transplanted into new families and new realities.
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I would say this would classify as a downward comparison as the person is talking about Mark who has a poorer job situation than him and this could be used to bolster the speaker's ego or to knock poor Mark or could just be an observation.