An irreversible binomial idiom is a two-term phrase where they must go in a specific order to be idiomatically correct. For instance, it would sound odd to say that pirates fly a flag with the "crossbones and skull". Can you guess the second part of these irreversible binomials?
Interesting. I took the ones from Wikipedia that I instantly recognized from my own culture and looking it up on nGram it seems that the way they are on the quiz is generally five to ten times more common than reverse. Maybe I should do a second version of this quiz and give idioms where you have to decide whether they're the "right way around" according to nGram and Wikipedia. Then there's no confusion and people will be angry when they see "cheese and macaroni".
*Peaches and Plums
*Milk and Cookies
*Law and Justice
*Peas and Corn
I usually hear *answer* and Knife, so I'm not sure if that idiom is irreversible.