房东要求租客找一个担保人来确保租金按时支付。

The landlord asked the tenant to find a ___surety to ensure the rent is paid on time.

银行要求他为贷款提供担保。

The bank required him to provide ___sureties for the loan.

他对自己的决定充满把握。

He acted with complete ___certainty about his decision.