– Can you play with us, Tina?
-- ____, I have ____ my sister. She can’t be at home alone.

– Can you play with us, Tina?

-- ____, I have ____ my sister. She can’t be at home alone.

A．Sure; to babysit                         B．Sure; babysit

C．Sorry; to babysit                        D．sorry; babysit

– Can you play with us, Tina?
-- ____, I have ____ my sister. She can’t be at home alone.

1. A.
   Sure; to babysit
2. B.
   Sure; babysit
3. C.
   Sorry; to babysit
4. D.
   sorry; babysit

--- Can you play tennis with us now?

--- _____. I have to finish my homework first.

A. Yes, I can’t.  B. No, I mustn’t.  C. I’m afraid not.  D. Of course