医生签署文件证明这位患者已经完全康复。

The doctor ___certifies that the patient has fully recovered by signing the document.

完成培训后，这个机构将认证你为合格的急救员。

After completing the training, this institution will ___certify you as a qualified first aider.

医生需要认证这份出生证明的真实性。

The doctor needs to ___certify the authenticity of this birth certificate.