Complex sentence: In 1959 the plans were again revised and in 1960 a new committee was created, which suggested building a third line between Grefsen and Bestun for freight trains to connect between the eastern and western lines.
Split into simpler sentences: In 1959 the plans were revised and in 1960 a new committee was created. They suggested building a third line between Grefsen and Bestun for freight trains to connect between the eastern and western lines.