Complex sentence: President Lyndon Johnson had picked Kerr to become secretary of Health, Education and Welfare but withdrew the nomination after the FBI background check on Kerr included damaging information the agency knew to be false.
Split into simpler sentences: President Lyndon Johnson had picked Kerr to become secretary of Health, Education and Welfare. But Johnson withdrew the nomination after the FBI background check on Kerr included damaging information the agency knew to be false.