Answer: The correct revision is: “Growing up, my favorite toys were Legos and a chemistry set; to me, the most fun of all was using the chemicals to melt the plastic bricks.”
Explanation: This revision places the modifiers correctly by starting with an introductory phrase that sets the context (“Growing up”), followed by a comma and then the main clause (“my favorite toys were Legos and a chemistry set”). The sentence then ends with another semicolon and a phrase that adds additional information (“to me, the most fun of all was using the chemicals to melt the plastic bricks”).
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