In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

Q: A crystal is a solid whose molecules ( or atoms ) are arranged in a repeating pattern .

A: A crystal or crystalline solid is a solid material whose constituents ( such as atoms , molecules , or ions ) are arranged in a highly ordered microscopic structure , forming a crystal lattice that extends in all directions .
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Q: A running gag is an humorous joke or reference that is used several times in a work or series of works .

A: A running gag , or running joke , is a literary device that takes the form of an amusing joke or a comical reference and appears repeatedly throughout a work of literature or other form of storytelling .
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Q: He is the guitarist for both Slipknot and Stone Sour .

A:
He is one of two guitarists for the American heavy metal band Slipknot , and the former lead guitarist for the American alternative metal band Stone Sour .
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