-You should do more to keep fit.
-B (That's a good idea.)
-That's four pounds fifty please.
-C (Here you are)
-Is it OK for me to use your toilet?
-A (Sure, go ahead)
-How are you feeling?
-C (My back hurts)
-I've just failed my driving test!
-B (Poor you!)
-I'm sorry but dropped your tablet and broke it
- C (it's all my fault)