这位新顾问在谈到市场策略时，显然很懂行。

The new consultant clearly ___knows ___what she ___is ___talking ___about when it comes to market strategy.

在给出建议之前，要确保你自己是了解情况的。

Before giving advice, make sure you ___know ___what ___you ___are ___talking ___about.

很多政客说话很自信，但很少有人真的言之有物。

Many politicians speak confidently, but few actually ___know ___what they ___are ___talking ___about.