Choose the correct anwser

11 Americans              the tradition of volunteering and helping one another since the early days of the country.

     A. have had            B. has had                     C. had                    D. to have

12.My brother and I       a white tiger already.

     A. have seen           B. has seen              C. see                    D. are seeing

13.I       blood twice, and       presents to sick children in the hospital recently.

     A. donate - give                                                B. donated — gave

     C. have donated - have given                        D. have donated - gave

14.How many novels       Charles Dickens         ?

     A. does - write       B. have - written          C. did - written            D. did - write

15.We       to Ha Noi several times, but last summer we      there by train.

     A. flew - went                                                   B. has flown - went        

     C. have flown - have gone                              D. have flown - went