not supposed to

(It's) not supposed to.

 and (Someone's) not supposed to.
a phrase indicating that someone or something is not meant to do something. (Often with a person's name or a pronoun as a subject. See the examples.) Fred: This little piece keeps falling off. Clerk: It's not supposed to. Bill: Tom just called from Detroit and says he's coming back tomorrow. Mary: That's funny. He's not supposed to.
See also: not, supposed
References in classic literature ?
When we meet at meals, I am not supposed to allude to the fact that he has been out in that crazy place.
We are not supposed to visit it," he said; "but the great ones cannot hear and if we keep well out of sight they need never know that we have been there.
The Mahars of Phutra are not supposed to eat human flesh, yet slaves are brought here by thousands and almost always you will find Mahars on hand to consume them.
Most awed of all were Joan and Sheldon, but, being whites, they were not supposed to be subject to such commonplace emotions, and their task was to carry the situation off with careless bravado as befitted "big fella marsters" of the dominant breed.
He knew a self-respecting, square-dealing man was not supposed to take his stenographer to luncheon.
The lady was not supposed to do anything in return; she might at most smile upon her knight or drop her glove, that he might be made happy by picking it up.
This turnkey had given him to understand that he was lodged, like some few others in the jail, apart from the mass of prisoners; because he was not supposed to be utterly depraved and irreclaimable, and had never occupied apartments in that mansion before.
Although Jurgis did not understand it all, he knew enough by this time to realize that it was not supposed to be right to sell your vote.
Is it true that you are not supposed to wash mushrooms?
Summary: The race for Egypt's first president after ousted autocrat Hosni Mubarak was not supposed to look like this.
First, under Canon Law, priests are not supposed to belong to political parties and are prohibited from running for, or holding, public office, unless there is serious necessity for the "protection of the rights of the Church or the promotion of the common good.
I had to explain to my kid that some teams don't follow the rules, and play kids in positions they're not supposed to.
It's not supposed to be a trade, it's supposed to be we save lives and we all come home and feel good about it.
Approximately 27% of the students surveyed reported setting something on fire that they were not supposed to at least once during the previous 12 months before the survey.
The short answer is that non-profit, 501(c)(3) groups exist to serve the public good and are not supposed to be focused on partisan politics.