Complex sentence: Lam Ching-ying was recommend to the director by Sammo Hung to play the main role, the director had seen Lam before on The Prodigal Son which the director had worked on.
Split into simpler sentences: Lam Ching-ying was recommend to the director by Sammo Hung to play the main role. The director had seen Lam before on The Prodigal Son which the director had worked on.