menacing

The dark, menacing clouds on the horizon suggested that a severe storm was approaching.

(Chinese) 地平线上阴暗且带有威胁性的乌云预示着一场严峻的暴风雨即将来临。

The bodyguard gave the intruder a menacing look that made him immediately step back.

(Chinese) 保镖给了闯入者一个威胁的眼神，吓得他立刻往后退。