在正式晚宴上，他的举止总是相当拘谨。

His manner was always rather ___stiff at formal dinners.

经理那不苟言笑的举止让新员工们很紧张。

The manager's ___stiff demeanor made the new employees nervous.

在她的演讲中，她始终保持着一本正经的正式口吻。

In her speech, she maintained a ___stiff and formal tone throughout.