Complex sentence: The State Department normally has two deputy secretaries of state and six undersecretaries; all but two of those positions are currently vacant; And as of March 2017 no nominations had been submitted for any of those senior positions.
Split into simpler sentences: The State Department normally has two deputy secretaries of state and six undersecretaries; all but two of those positions are currently vacant. As of March 2017 no nominations had been submitted for any of those senior positions.