Complex sentence: However, in order to preserve his place in the royal succession, Bertil and Lilian did not marry for decades, but lived together discreetly, as a fully private arrangement, from the 1940s until their marriage was announced and took place in 1976.
Split into simpler sentences: However, in order to preserve his place in the royal succession, Bertil and Lilian did not marry for decadesl. They lived together discreetly, as a fully private arrangement, from the 1940s until their marriage was announced and took place in 1976.