The girl wore a menacing expression on her face.
The menacing figure loomed in the shadows, sending shivers down my spine.
In your sentence, the word 'grumbling' is the main verb('was' is the auxiliary verb).
I was menacing to the store/back home
Sentence for menacing in the 5th degree in colorado
The timid boy approached the menacing dark man towering in the doorway.
" The hero sprang into action to save the town from the menacing villain."
As ominous means baleful, forbidding, menacing, minacious, and so on, it is not the correct word to use in the sentence.
The menacing sky reflected Todd's mood; dark and unpleasant.
The sentence for menacing in the 2nd and 3rd degree varies by state. The sentence of menacing in the 2nd and 3rd degree could be some jail time, a fine, or probation.
Yes, the word grumble is a noun, a word for the sound that the bear was making. The word grumbling is the main verb, the action of the bear.
To be baleful means to be threatening or menacing. For example, "The bull sent a baleful glance at the intruder as he munched on a blade of grass".
menacing