tai was a Cantonese speaker, but Ma yong zhen was a  Mandarin production. However, unlike Lee, who spoke Cantonese during  shooting and was dubbed in Mandarin later on, Chen actually learned  how to say his lines in Mandarin, even though he wasnt completely  sure what they meant. Ironically, actor Cheung Pui San was the  Mandarin voice actor for both Lee and Chen.