As busy as a bee
Definition 1 of 1
Pro Tip 1/3Positive Tone
Expresses admiration for someone's energy or commitment to work. 
With her new project, she's as busy as a bee and loving every minute!
Pro Tip 2/3Visual Imagery
Evokes the picture of a bee's constant movement, suggesting tireless activity. 
Whenever I visit the kitchen, he's there as busy as a bee, cooking for the family.
Pro Tip 3/3Specific Activities
Best used to describe someone engaged in physical or visible tasks, not abstract ones. 
She's been as busy as a bee gardening all weekend.