21.   ---I’m afraid you have the wrong number.

---Sorry!     .

A. See you later                         B. I didn’t know that

C. Hold on, please                       D. I hope I didn’t bother you

22.   According to the law, everyone is     before he or she is found guilty.

A. innocent          B. initial           C. independent       D. just

23.   ---Jack failed the driving test again.

---The question is      we can help him avoid making the same mistake.

A. why               B. how               C. what              D. that