Complex sentence: The CCE&HR was established in 1891 but construction was delayed for more than a decade until, in 1900, it became a subsidiary of the Underground Electric Railways Company of London Limited (UERL) which funded the construction works.
Split into simpler sentences: The CCE&HR was established in 1891 but construction was delayed for more than a decade. In 1900, it became a subsidiary of the Underground Electric Railways Company of London Limited (UERL) which funded the construction works.