我借了钱给他，我需要一个欠条。
wǒ jièle qián gěi tā ， wǒ xūyào yígè qiàn tiáo 。
I lent him money, and I need a receipt for the loan.
他给我写了一张欠条，说明他会还钱。
tā gěi wǒ xiě le yīzhāng qiàn tiáo ， shuōmíng tā huì huán qián 。
He wrote me a receipt for the loan, stating that he would pay it back.
在借钱的时候，最好有欠条作为证明。
zài jiè qián de shíhòu ， zuìhǎo yǒu qiàn tiáo zuòwéi zhèngmíng 。
When lending money, it's best to have a receipt for the loan as proof.