问题
选择题
___________for his good skill, this doctor has a lot of visitors calling for help all the time.
A．Knowing
B．To know
C．Known
D．To have known
答案
答案：C
题目分析：句意为：由于他的技术出名，当时这个医生有很多游客前来求助。这是一个独立结构，应该用分词短语作状语，由于其与句中逻辑主语是被动关系，应用过去分词形式，故选C。