Question

【题目】When Madam Curie did the science experiment again, she was more careful ________ she had made a mistake.

A．what B．when C．which D．where

Answer 1

【答案】D

【解析】考查状语从句。句意：当居里夫人两次做实验时，在以前出错的地方更加的小心。根据again可知以前出过错，故是出错的地方，因此选D项。