Complex sentence: Liu, however left the series in 2004 due to co-star Frankie Lam's marriage to actress Kenix Kwok and ultimately never returned to the series even when it concluded in January 2005.
Split into simpler sentences: Liu, however left the series in 2004 due to co-star Frankie Lam's marriage to actress Kenix Kwok. Lam ultimately never returned to the series even when it concluded in January 2005.