他的演讲真正令人印象深刻，让观众肃然起敬。

His speech was truly ___impressive and left the audience in awe.

我们在徒步旅行中看到了一些令人惊叹的山景。

We saw some ___impressive mountain views during our hike.

她这学期在成绩上的进步非常令人钦佩。

Her improvement in grades this semester has been very ___impressive.