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circus - n. a traveling show, often performed in a tent with animals, clowns, ...
acrobat - n. someone who performs difficult and dangerous acts (usually at a circus)
spin - v. to turn or cause someone or something to turn around repeatedly
unicycle - n. similar to a bicycle but has only one wheel
negative - adj. thinking about the bad qualities of someone or something
essential - adj. extremely important and necessary
roll - n. an act of turning over and over
expose - v. to experience or to be influenced by something
