问题
选择题
She is the only one of the persons ________ from the mistakes.
A．whom I know have learned
B．whom I know has learned
C．I know who has learned
D．I know who have learned
答案
答案：C
考查定语从句，one of+ 复数名词，前面被the (only )修饰时谓语动词用单数形式，所以选C, I know 做插入语，who 在定语从句中做主语，句意：他是我认识中的唯一一个从错误中学习的人。