Complex sentence: The second line of DECstations began with the DECstation 3100, released on 11 January 1989, were the first commercially available RISC-based machines built by DEC. The 3100 was followed by a cost reduced 2100.
Split into simpler sentences: The second line of DECstations began with the DECstation 3100, which was released on 11 January 1989. Digital Equipment Corporation The 3100 was followed by a cost reduced 2100.