Playing golf with clients is one way to 'mix business with pleasure'. [=to do something enjoyable that is related to your work]
I accidentally 'mixed up' the two files. [=I put each of the files in the place where the other one should have gone]
He 'got mixed up in' a plan to destroy the government. [=he became involved in a plan to destroy the government]
(..) Right. At least not when there's alcohol involved. True. Bridge and booze simply don't mix. You have to be able to handle it. - I can handle it. - Of course you can. Is Mordur in? (..)2015 Virgin Mountain