Complex sentence: In Classical Latin it was used to confirm a previous sentence or, ironically, to state its contrary; but both usages have pretty much been lost over the course of the years, leaving the simpler meaning explained above.
Split into simpler sentences: In classical Latin it was used to confirm a previous sentence or, ironically, to state its contrary. Both usages have pretty much been lost over the course of the years, leaving the simpler meaning explained above.