Complex sentence: It transfers road vehicles across the Channel Tunnel, with passenger vehicles being carried in closed double-deck car-carriers and HGVs in semi-open wagons, with a separate passenger carriage for the drivers.
Split into simpler sentences: It transfers road vehicles across the Channel Tunnel, with passenger vehicles being carried in closed double-deck car-carriers. HGVs are carried on semi-open wagons, with a separate passenger carriage for the drivers.