大全562弱问

562.One reason why more young people lose their virginity during the summer than at other times of the year undoubtedly is because school vacations give adolescents more free time.

(A) One reason why more young people lose their virginity during the summer than at other times of the year undoubtedly is because

(B) If young people lose their virginity more during the summer than other seasons, it is undoubtedly because

(C) One undoubtable reason that young people lose their virginity more during the summer than other times is

(D) One reason more young people lose their virginity during the summer than at other times of the year is undoubtedly that？（D）

(E) Young people lose their virginity more often during the summer undoubtedly

我的问题是undoubtedly不是副词吗？be 动词后面可以跟副词吗？

还有c的选项undoubtable 是不是不存在这个单词？好像字典里查不到

可能是我的问题弱智了点,哪位可以回答我一下啊，谢了

对，“undoubtable”这个词不存在

副词可以修饰谓语动词