ZHI (之) and DE(的) can both be used to link a modifier and its head. For example:
政府之成立 the foundation of government
证人的出现 the appearance of witnesses
ZHI is a function word mainly used in Old Chinese and Middle Chinese, while DE(的) appeared in late Middle Chinese and mainly used in Early Chinese. Although appeared quite late than ZHI, DE replaced some usage of ZHI in Early Chinese.
In Modern Chinese, DE is the most common used function word. For example, in 2013, there are 1300 headlines of People's Daily have used DE or ZHI. The usage of DE is 34.58% (1257 headlines have used DE) while ZHI is 9.57% (53 headlines have used ZHI). People's Daily can be categorized to written Chinese text. In spoken Chinese, ZHI seldom appears. Therefore, the differences between DE and ZHI mainly belongs to language style. ZHI is used in written Chinese while DE is used in both written and spoken Chinese.
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