问题
选择题
.If _____,the experiment will be successful.
A．carefully doing
B．it done carefully
C．carefully done
D．doing carefully
答案
答案：C
考查状语从句的省略。主语the experiment与do之间是被动关系，所以用过去分词done，句意：如果这个实验被认真做的话，它会成功的。carefully done前省略了it is，所以选C。