Complex sentence: Arriva North West put a proposal to the Competition Commission of substantial investment for Gillmoss if they withdrew their stipulation to sell the depot and FirstBus's acquisition of Strathcylde Buses in 1996 when the Monopolies and Mergers Commission (MMC) ordered it to sell a depot.
Split into simpler sentences: Arriva North West put a proposal to the Competition Commission that it was willing to invest substantially in Gillmoss if they withdrew their stipulation to sell the depot. It used FirstBus's acquisition of Strathclyde Buses in 1996 when the Monopolies and Mergers Commission (MMC) ordered it to sell a depot.