他在金融领域的专业知识帮助我们避免了投资风险。

His ___expertise in finance helped us avoid investment risks.

这位工程师在解决复杂技术问题方面展现了高超的专业技能。

The engineer showed impressive ___expertise in solving complex technical problems.

我们需要一位医生的专业意见来诊断这个病例。

We need a doctor's ___expertise to diagnose this case.