Complex sentence: Furthermore, because the Sunnyside Station is the last stop on the NW line the trains are often packed to capacity, although this may be alleviated by the introduction of 4-car trains in the future.
Split into simpler sentences: Furthermore, because the Sunnyside Station is the last stop on the NW line the trains are often packed to capacity. Although this may be alleviated by the introduction of 4-car trains in the future.