expunction

例句：

1. 2.
   法律
2. 3.
   在数学中
3. 1. The court ruled that the defendant's expunction was justified.
   法院裁定被告的免责是合理的。
4. 2. The student had to pay for the damage done during the exam.
   学生不得不为考试期间造成的损坏负责。
5. 3. The math teacher explained the concept of expunction in his lesson.
   数学老师在他的课上解释了开方的概念。