本单为一式三联：第一联为出票联，由出票单位留存；

This form is in triplicate: the first sheet is for issuing, kept by issuing unit;

youdao

本单为一式三联：第一联为出票联，由出票单位留存；

This form is in triplicate: the first sheet is for issuing, kept by issuing unit;

youdao