Re-written, the sentence with the correct relative clause would read:
"The musician whose music was folk to the Americans for the next thirty-five years is called Woody Guthrie."
A relative clause is a clause that is attached to a relative pronoun such that one has more information about the person or thing mentioned.
Notice how the new sentence clarified the role of Woody Guthrie and his music as well as its impact on the American? that is the effect of a Relative Clause.
Learn more about Relative Clauses at:
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