蜜蜂在花丛中嗡嗡作响。

The bees were ___humming around the flowers.

他一边洗碗一边哼着歌。

He was ___humming a song while washing the dishes.

咖啡馆在午餐时间总是热闹非凡。

The cafe is always ___humming with activity during lunch hours.