Complex sentence: In 1991 she delivered the Jefferson Lecture under the auspices of the National Endowment for the Humanities, and in 2004 she received the National Humanities Medal awarded by the President.
Split into simpler sentences: In 1991 she delivered the Jefferson Lecture under the auspices of the National Endowment for the Humanities. In 2004 she received the National Humanities Medal awarded by the President.