I know all those except stay shtum and putpocket (unless it means thrifty).

shtum means silent - it's a yiddish word. But "schtumm" is also the german world for silent. putpocket is the reverse of pickpocket - people who secretly put something in your pocket without your knowledge.

Hmmm, never heard of putpocket...maybe because no one's tried to put $ in my pocket in....well, EVER...hahah

lol. I am signed up with a nifty little service called One Word a Day - I get a vocabulary every day with 3 different definitions and then I can guess which one is correct. I know 99% of the words and idioms or guess the meaning correctly, but sometimes I get one that I really didn't know like putpocket.

I am not sure of the first, I am unsure what the lesson was on the second (maybe I just know it too well?) amd never heard of the 3rd!  I suspect it is the same as leading a horse to water?

double Dutch - nonsense, gobbledygook etc. If you ever heard dutch it is quite easy to imagine

I must see a man about a dog - use the bathroom

to teach someone to suck eggs - to give advice to someone about a subject that they already know more
about than you

Ahhh...idioms...my favorite part of any foreign language...or my own, for that matter.

How about:  "um die ecke bringen"  or "uebung macht den meister"  or "ein...zwei...sofa!"  (Sorry, still got Fasching on my mind).

Ok, so I learned one!  Althought I have never heard it used.

http://en.wikipedia.org/wiki/Teaching_grandmother_to_suck_eggs

I always thought that the expression was, "I'll teach you to suck eggs" spoken in the same tone of voice one would use to scold a child:  like, "I'll teach you to hit your sister".  In my mind it was always tightly connected to Johnny Cash's song, "That dirty old egg-suckin' dog".

"I have to see a man about a dog" also works with "a horse". My dad used to say that. I know most of those phrases....what's a Salt Cellar? I know what a fruit cellar is, my grandparents had one.

Another, more local term, is "Tallulah", as in "She's a Tallulah!"; most commonly meaning a brash, overbearing woman.

salt cellar is the same as salt shaker

"Got to see a X about a X" is just a term used to mean you have something to do.

And don't forget the old "Dutch Courage" or the ever popular "Dogs Bollocks"

I have to admit that I don't really know that much swearing or derogatory terms besides the commonly known. Go on.. lol the most fun in any language are those idioms.

Swearing?! perish the thought (granted IRL i'll pop out a swear word per sentance, but online i try to remain a little civil, people get confused easily).

Dutch Courage - An alcoholic drink prior to something stressful (aka, asking a girl out etc). Possibly from the times of the Black death. London was often quarentined, Dutch merchants were one of the few who would breach the lines, usually after having a drink to steady the nerves.

Dogs Bollocks - Used to refer to something thats great (Sins of a Solar Empire is the dogs bollocks), born from the question why do dogs continuously lick their balls? Nobody knows...but they must be great to keep doing it.