Complex sentence: The National Education Association (NEA) is the largest professional organization and largest labor union in the United States, representing public school teachers and other support personnel, faculty and staffers at colleges and universities, retired educators, and college students preparing to become teachers.
Split into simpler sentences: The National Education Association (NEA) is the largest labor union in the United States. It represents public school teachers and other support personnel, faculty and staffers at colleges and universities, retired educators, and college students preparing to become teachers.