Complex sentence: The attempt fails, but Ying Zheng is furious when none of his associates attempt to stop the assassin and he is forced to kill Jing Ke himself, and further saddened when Lady Zhao returns to Qin only to retrieve Jing Ke for burial.
Split into simpler sentences: The attempt fails, but Ying Zheng expresses his fury when his associates make no attempt to stop the assassin and he is forced to kill Jing Ke himself. He is further saddened when Lady Zhao returns to Qin only to retrieve Jing Ke for burial.