英语翻译she would point out if they had mastered and declared fi

she would point out 主句：她会指指出……
if 引导从句,表示假设.
they had mastered and declared firmly 从句中的主句,他们掌握了的,并断定……
they could learn what they had missed .宣布的内容.
what they had missed learn的内容.他们错过的东西.
这个句子就是从句套从句,从句太多了,以致于结构稍显复杂.
基本没个动词免都跟着自己的从句.
这样看就应该能理解了.

这是完整的句子：
When students receive less than a perfect test score she would point out what they had mastered and declare firmly they could learn what they had missed.
这是翻译：
当学生的考试成绩不理想时，她就...