5. about to

5. about to

About + infinitive (with to) means 'going to very soon'; 'just going to'.
    Don't go out now - we're about to have lunch.
    I was about to go to bed when the telephone rang.


Not about to can mean 'unwilling to',
    I'm not about to pay 100 dollars for that dress.






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4. About and On

4. about and on

Compare:
- a book for children about Africa and its peoples
   a textbook on African history


- a conversation about money 
  a lecture on economics 

We use about to talk about ordinary, more general kinds of communication.
On suggests that a book, talk etc is more serious, suitable for specialists.

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