Complex sentence: On June 4,2008, he was confirmed as the new U.S. ambassador to Zambia; he left his post in Liberia on July 11, and took up the post in Zambia on September 19.
Split into simpler sentences: On June 4,2008, he was confirmed as the new U.S. ambassador to Zambia. He left his post in Liberia on July 11, and took up the post in Zambia on September 19.