1. as busy as a bee - very busy.
  2. big fish in a small pond - an important person in a small place.
  3. have bigger fish to fry - to have other more important things to do.
  4. fish out of water - meaning someone feels out of place.
  5. shooting fish in a barrel - something that is very easy to do or effortless.
  6. fish for something - to try to get information from someone.
  7. a woman needs a man like a fish needs a bicycle(slogan) - a feminist slogan, suggesting that men are superfluous to women's needs.
  8. teach fish to swim(proverb)- tell someone something which he/she has already known.
  9. as strong as a horse - very strong.
  10. beat a dead horse - to continue fighting a battle that has been won.
  11. horse trade - to bargain in a hard and skillful way.
  12. as weak as a kitten - weak, sickly.
  13. a fraidy-cat - someone who is easily frightened.
  14. play cat and mouse - to tease or fool someone.
  15. rain cats and dogs - to rain very hard.
  16. as poor as a church mouse - very poor.
  17. buy a pig in a poke - to buy something without seeing it.
  18. in a pig's eye - unlikely.
  19. make an ass of yourself - if you behave so stupidly that you appear ridiculous, you make an ass of yourself. 
  20. bee's knees - to say that someone/something is the bee's knees means that you think they are exceptionally good.

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