Substitute one word for the italicised expression.

When her teacher calls her a person who cannot be corrected, she laughs at herself.

incorrigible

The word that can substitute the italicised expression "person who cannot be corrected" is incorrigible.

• Obedient means compliant with the orders or requests of others.
• Reformable means capable of being corrected or improved.
• Incorrigible means incapable of being corrected or amended.
• Manageable means able to be controlled or handled.

Incorrigible is the most appropriate word for the given expression because it specifically refers to someone who is incapable of being corrected or amended. It is derived from the Latin word incorrigibilis, meaning "not to be corrected."