endorsement of bill of lading

例句：

1. 1. He signed the contract with a written endorsement.
   他以书面形式背书了这份合同。
2. 2. The bank required the signatures of all parties to the agreement for the endorsement to be valid.
   银行要求所有协议方的签名，才能使背书有效。
3. 3. The endorsement is crucial as it ensures that the transaction is legitimate and secure.
   背书至关重要，因为它确保交易是合法的和安全的。