backing card

例句：

1. 1. This backing card is crucial for our project's success.
   这张背书卡对我们项目的成功至关重要。
2. 2.The company issued a backing card to the new manager.
   公司向新任经理发放了背书卡。
3. 3. The backing card will be used to verify the authenticity of the signature on the contract.
   背书卡将被用来验证合同上签名的真实性。