Complex sentence: Central Islip station was originally built on November 14,1873, on the southeast corner of Suffolk County Roads 17 & 100 as a replacement for the former 1842-built Suffolk station on Islip Avenue (now NY 111, then Fifth Avenue).
Split into simpler sentences: Central Islip station was originally built on November 14,1873, on the southeast corner of Suffolk County Roads 17 & 100 as a replacement for the former Suffolk station. Suffolk Station was originally built on July 14,1842 on Islip Avenue (now NY 111, then Fifth Avenue).