Every language has individual idioms, which are not just language specific, but also serve to reflect cultural values and perceptions. A description like this is a fancy way of describing the function of a phrase like: go fly a kite or kick the bucket. Most people would understand what these phrases mean, however if they were translated into another language, they would be incomprehensible for a native speaker. Over the year I have collected my favorite German idioms which become nonsense in English. Some of these I have heard on my own, others seen in poorly designed advertisements implementing English, and others from stories of people using such phrases in English class. A short description of the original meaning in German follows.

I have the nose full – to be fed up with something
Keep your ears stiff – stay aware
I believe I spider – to think oneself crazy, most times used ironically
One could steal a horse with him – thick as thieves
Life is not a pony farm – life is not a game, I have heard this multiple times from Germans
To bite grass – to die
To give up the spoon – to die, this one and comes from knights who would heir their spoons to their follower before dying: a spoon signifying a dining place in a castle or fortress
I can't bake it! – to not be able to finish something
With him is not good cherry eating – German grandmothers implement this to describe a poor conversationalist
I make myself, yourself, nothing out of the dust – this one means to leave quickly