English: Could you get me a beer when you go to the bar, please?
Czenglish: Would you like a concrete one?
English: I’d prefer it is liquid.
Czenglish: No! I meant what kind of beer do you want?
English: Ah, you should have asked if I want a specific one 🙂
In English concrete only means specific when something is firmly fixed in place. Typically this would be used with plans to show something will definitely happen.
– Do you have concrete plans for the weekend?
– Yes we are going to Austria on Saturday morning.