a baleful look; forbidding thunderclouds; his tone became menacing; ominous rumblings of discontent; sinister storm clouds; a sinister smile; his threatening behavior; ugly black clouds; the situation became ugly.

• 恶毒的眼神；可怕的雷雨云；他的声音变得恶毒了；不吉祥的怨言；不祥的暴风云；险恶的微笑；他那危险的行为；不祥的乌云；局势变得危险了。