《纯正英语一分钟》第220课：OK

      I like the expression ‘OK’. I don’t know why. It’s so useful. Everyone in the world understands what it means. It must be the only word that everyone knows. Is it a word or is at an abbreviation? We spell it ‘okay’ but abbreviate it as ‘OK’. I wonder how many meanings it has. You can ask if someone is OK, if they are ill; you can ask if someone understands a question or instructions using OK; you can even let someone know ‘enough is enough’ by saying OK. If you say something is OK, it means you don’t really like or dislike it. In fact, sometimes, if you say, “He’s OK” or “She’s OK, it means you don’t really like them. I think okay is also a verb. I have heard people say, “It’s OK, John okayed it”.