Complex sentence: St Paul's Church opened in 1981, and is used by both the Church of England and the Free Churches, which, before it was built, had collaborated in a churchless religious venture known as the' Roundshaw Experiment'.
Split into simpler sentences: St Paul's Church, opened in 1981, and is used by both the Church of England and the Free Churches. Before it was built, it had collaborated in a churchless religious venture known as the' Roundshaw Experiment'.