Busy bee

From: http://www.bbc.co.uk/worldservice/learningenglish/language/2014/04/140417_todays_phrase_busy_bee.shtml

Honey bees in a hive

Very busy bees

Today's Phrase

A very simple phrase today. Bees look like very busy animals, so if you say you are as busy as a bee, or call yourself a busy bee it means you're very busy!
Examples:
I've been a really busy bee this morning. I've been to the shops, paid my bills, had a haircut and even been for a run.
Frank is such a busy bee. He's always doing about five projects at once! He needs to take it easy.

Take note

If you have a bee in your bonnet about something, it means you are obsessed by that thing - you can't stop thinking about it.
Example:
He's got a bee in his bonnet about fast cars. He talks about them all day long!

Interesting fact

Bees' wings move very fast. They move them up and down around 200 times a second.