shīfù cóng xiāngzi lǐ náchū yītiáo xīn liànzi ， xiānbǐ le bǐ chángduǎn ， zài zhuāngshàngqù 。

师傅从箱子里拿出一条新链子，先比了比长短，再装上去。

The repairman took a new chain from his box, first compared the length, then put it on.