问题
选择题
The rescuers _______ to work as soon as they arrived at the spot of the accident.
A．set out
B．set off
C．set up
D．set in
答案
A
题目分析：句意：救援人员一到出事地点，就开始工作了。使用：Set out to do sth.开始着手做…, B. set off成分，引发，引爆， C. set up建立，D. set in嵌入，所以选A。