students and spelling

I'm still slogging through midterms. One comprehension question related to the first episode of "Three's Company" asks about what Mrs. Roper claims to be the reason for the crack in the Ropers' ceiling. The correct answer is "the earthquake," but several students have spelled the word as "earthquack," which sounds almost as though the earth were an enormous duck... or Hwang Woo-seok's cranium.


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