问题补充：
is to be done is to carry it out smoothly since the decision has been made．
A. What; how
B. Where; how
C. When; what
D. Where; what
答案：
(答案→)A. What; how
B. Where; how
C. When; what
D. Where; what
解析：考查从句，从句is to be done缺少宾语，所以选What，句子to carry it out smoothly不缺少成份，所以选how，句子意思“自从下定决心将要做什么是怎样顺利执行”，所以选A
