问题补充:
What great trouble the boy his father to give up smoking!
A. had to persuade
B. had persuaded
C. had persuading
D. had persuade
答案:
A. had to persuade
B. had persuaded
(答案→)C. had persuading
D. had persuade
解析:句意:这个小男孩在说服他的父亲放弃吸烟是多么的困难。这里是短语have trouble in doing做某事有困难;这里省略了介词in;这里是感叹句,被感叹的词是名词trouble所以用what,根据句意故选C。