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surname; family name; last name
日本で一番多い苗字は佐藤だと言われている。
It is said that the most common surname in Japan is Sato.
結婚して苗字が変わるのは手続きが大変だ。
Changing your surname after marriage involves a lot of paperwork.
同じ苗字の人がクラスに三人もいる。
There are three people with the same surname in the class.