A. a so dreadful
B. so dreadful a
C. such dreadful a
D. a such dreadful
A. mustn't you
B. haven't you
C. have you
D. didn't you
A. will not have happened
B. did not happen
C. would not have happened
D. had not happened
A. Mark Twain
B. Mark Twain's
C. that of Mark Twain
D. those Mark Twain wrote