May I go to a trip? Yes，you may. (　　)________

–May I go to the concert with you?

– I’m afraid not ______you have a ticket, because I have only one.

A. since        B. if        C. unless    D. though

- May I go to the movies with you?
- I'm afraid not ，        you have a ticket, because I have only one.
A． if                    B. unless                C. though

If you go to a supermarket and find that there is no cashiers (收银员), would you still pay (付钱) for your things? People in our   1  are having a test of honesty(诚信测试) now． The supermarket here has a special area． This area sells    2   things like pens and knives． People need to scan (扫描) their things, and put the    3    into the cash desk all by themselves．   4   watches them． By now, the supermarket runs（经营） very   5   ． People say they enjoy the feeling of being honest．
Once (又一次) I go to the supermarket to buy a note book． When I am ready to pay, I find I have no    6    on me． I am just going to put the note book   7  when a neighbour of mine sees me． He knows what my    8   is． And he says he will be glad to   9  me five yuan． I thank him and pay the note book    10    the money．
Do you think the supermarket is doing a great job? And will you be glad to pay when you are in such a supermarket?

— May I go to the concert with you?

— I’m afraid not ____ you have a ticket, because I have only one.

A. since　　 B. if　　 　 C. unless　　 　 D. though