默默 (mò mò): в молчании

During the time his mother was seriously ill, he silently kept watch by her bed every day and never complained to the family once.

She silently placed a cup of hot tea on my desk, then turned and left without saying anything.

After the earthquake, many volunteers quietly came from all over and worked continuously in the ruins for three days.

He silently endured his colleagues' mockery and devoted all his energy to research, eventually making a breakthrough.

After retiring, Grandpa quietly repaired appliances in the community for free and never left his name; the neighbors were all deeply moved.