A more thorough explanation:

Definition: Ingratitude is a lack of appreciation for a kind or generous act, especially for a gift received. In civil law, a gift can be taken back if the recipient mistreats the giver, such as attempting to harm the giver or refusing to provide them with necessary food.

Example: If someone gives you a gift, but you don't say thank you or show any appreciation, that is an example of ingratitude. In civil law, if someone gives you a gift and you mistreat them, such as trying to harm them or refusing to give them food when they need it, they can take back the gift on the grounds of ingratitude.

The examples illustrate that ingratitude is a lack of appreciation for a kind or generous act. In the first example, the person receiving the gift does not show any gratitude, while in the second example, the recipient mistreats the giver, which is considered an act of ingratitude in civil law.