Complex sentence: At youth, he came to Hing Fung Nin as a page boy and since he could not read or write, Chiang Kiu's father taught him the abacus and made him the first assistant boss of Hing Fung Nin.
Split into simpler sentences: At youth, he came to Hing Fung Nin as a page boy. Since he could not read or write, Chiang Kiu's father taught him the abacus and made him the first assistant boss of Hing Fung Nin.