What is the stalk when the smile fades?

This stalk means that I was originally happy, and suddenly I was hit, and I gradually became unhappy. Also often used as "smile fades away" and "smile fades away". But in fact, this sentence has been popular for a long time. In the software "See which star you look like", the original intention is to see which mortal enemy we look like the most. I didn't expect the kind-hearted netizens to test it with various expressions, and there were many funny things as a result.

The source of smile disappearing:

This word became popular as a network language around April 20 17, and the popular network relied on its magical "smile disappearing" expression pack.

After the word became popular, many related usages were derived. Common ones are "smile gradually becomes immoral", "smile gradually becomes abnormal", "smile gradually solidifies", "smile gradually becomes rampant", "smile gradually becomes social" and "smile gradually becomes social".

Usage example:

Use it when I am happy and suddenly punch, such as when the exam results come out.