Surnames are passed down from generation to generation, which is generally stable, while surnames change with the changes of feudal cities and official positions, so there will be several surnames in one's descendants or different surnames between father and son. Last name and first name together form a person's first name. "Surname, unified his ancestors from the exam; The surname is not divided by his descendants. " The surname is a racial number, and the surname is a branch of the surname. Since the Qin and Han Dynasties, surnames began to merge.
Last name is the same as last name.
First: they are all blood relatives.
Second: exogamy is a normal attribute.
Third: they are all a single-line successor group, that is, a paternal successor group.