Steven Cheung Chi-hang (Chinese: 張致恆)is a Hong Kong singer. Cheung was a member of the Cantopop duo, Sun Boy'z from 2002 to 2006, where William Chan joined in and the group was renamed Sun Boy'z. It was officially disbanded in December 2008. Steven Cheung Chi-hang (Chinese: 張致恆)is a Hong Kong singer. Cheung was a member of the Cantopop duo, Sun Boy'z from 2002 to 2006, where William Chan joined in and the group was renamed Sun Boy'z. It was officially disbanded in December 2008.