Complex sentence: A new company called Norton Villiers Triumph (NVT), managed by Dennis Poore, emerged in 1977 when the BSA group collapsed under its debts/Government help led to a merger with the Manganese Bronze Holdings subsidiary Norton-Villiers.
Split into simpler sentences: A new company called Norton Villiers Triumph (NVT), managed by Dennis Poore, emerged. When the BSA group collapsed under its debts, government help led to a merger with the Manganese Bronze Holdings subsidiary Norton-Villiers.