grimly, gloomily, darkly
dark, bleak, dreary
gloomily, sullenly, grimly, scowlingly
dimly, duskily, dim
gloomily, somberly, sullenly, grimly
Он мрачно посмотрел на нас и промолчал.
He looked at us grimly and said nothing.
Старик угрюмо кивнул и ушёл.
The old man nodded grimly and left.