______, the experiment is sure to succeed.A.If carefully doingB.If carefully doneC.If it done carefullyD.If it doing carefully
网友回答
B解析试题分析:考查非谓语动词。从四个选项可知，此题考查非谓语做状语，动词do和句子主语experiment之间是被动关系，所以排除A、D选项。而C选项中有主语但是谓语不完整，故B选项正确。属于连词+分词形式，此处也可以看做是if it is carefully done的省略。句意：如果认真做的话，这个实验肯定能成功。
考点：考查非谓语动词。