Complex sentence: In the course of thirty years or so Trafalgar House became a formidable international industrial and commercial undertaking, and during the final few years of its existence was consistently tabled as the largest contracting organisation in the UK, and one of the largest in Europe.
Split into simpler sentences: In the course of thirty years or so, Trafalgar House became a formidable international industrial and commercial undertaking. During the final few years of its existence, it was consistently tabled as the largest contracting organisation in the UK and one of the largest in Europe.