Complex sentence: He was appointed as special consultant to the Secretary of Agriculture, January 1968 to January 1969, and served as special area development assistant to Senator John L. McClellan from February 1971 until 1977.
Split into simpler sentences: He was appointed as special consultant to the Secretary of Agriculture, January 1968 to January 1969. He served as special area development assistant to Senator John L. McClellan from February 1971 until 1977.