Complex sentence: To help serve North America's booming transportation market the Group and Canada's Hatch Associates established a joint venture company in 1996 called Hatch Mott MacDonald after a long affiliation which first began when working together on Toronto's subway in the 1950s.
Split into simpler sentences: To help serve North America's booming transportation market the Group and Canada's Hatch Associates established a joint venture company in 1996 called Hatch Mott MacDonald. This followed a long affiliation between the two which began when working together on Toronto's subway in the 1950s.