I'd been trying to master mental arithmetic for years.  I kept practising, subtracting 33 from 3 times 11, or adding 3 to minus 3.  In the end it all came to nothing.

I went into a burger restaurant the other day and ordered a meal.  The girl behind the counter asked me if I wished to, "Go large".  I said, "Well, a little larger than when I came in, of course".