The nurse whose name is Mary assisted me the operation they day before yesterday.
A. perform
B. to performing
C. on performing
D. in performing
网友回答
A. perform
B. to performing
C. on performing
(答案→)D. in performing
解析：考查短语assist sb in doing sth “帮助某人做某事”。句意：名叫玛丽的护士前天帮助我做手术。