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When he was 10 years old, he killed his classmate and threw it into the well.

The next day, the body disappeared

At the age of 20, he killed his rival and threw it into the well.

The next day, the body disappeared

At the age of 30, he killed his boss and threw it into the well.

The next day, the body disappeared

At the age of 40, he killed his mother and threw it into the well.

The next day, the body did not disappear,

On the third and fourth day, the body is still...

[The joke is a little old, but the meaning is very profound. While at home, play less computer and spend more time with your parents, and love them more]