articulate

他的表达非常清晰，每个字都听得清清楚楚。

His ___articulate speech made every word crystal clear.

他能够清晰地表达复杂的科学概念。

He can ___articulate complex scientific concepts clearly.

她很难清楚地表达自己的想法。

She found it difficult to ___articulate her thoughts clearly.