她总是穿得很正式，言行举止都显得非常拘谨。

She always dresses in a ___buttoned-up manner and behaves very conservatively.

他的工作方式非常严谨，从不遗漏任何细节。

His ___buttoned-up work style ensures no detail is ever overlooked.

即使在紧张的会议上，她也保持冷静，始终不露声色。

Even in the tense meeting, she stayed ___buttoned-up and showed no emotions.