15. When Madam Curie did the experiment again, she was more careful where she _____ a mistake.
A.made | B.has made | C.was making | D.had made |
相关知识点
推荐套卷
15. When Madam Curie did the experiment again, she was more careful where she _____ a mistake.
A.made | B.has made | C.was making | D.had made |