Please attach proof of purchase when submitting your refund request to customer service.

向客服申請退款時，請附上購買證明。

Applicants must provide proof of employment history before the second interview.

應徵者在第二次面試前必須提供工作經歷證明。

The auditor asked for written proof that the invoice had already been paid.

查帳員要求提供書面證據，證明該發票已經付款。