Some situations during which 唱歌
"Let it go
Let it go
Can't hold it back anymore"
would be dangerous:

1) When 你 或者 someone else is controlling his/her process of egestion 或者 excretion.

2) When someone's school bus get missed.


3) When someone is trying to stop vomiting during a bus journey.

4)When someone's pet bird fly away from owner.

Please add something else 由 commenting. It's a type of funny article. So please 评论 for 更多 suggestions.