Answer: As we know, a simile is a literary device that involves a comparison between two distinctly related things using 'like' or 'as' in order to explain or elaborate them for a better understanding of the reader.
In the given simile, the author compares the 'sound of formidable words' with the 'sound of trapezes in full swing' which suggests that the author is experiencing a very hard time learning these words and connotes his negative mood. The word 'formidable' means 'something frightening or dreading' which suggests that the author was having a terrifying experience as supplemented by the phrase 'trapezes in full swing' implying that the words were confusing and difficult for him to learn.
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