Here are some ways to interpret it:
* Fake or insincere: The person is acting a role, putting on a facade to impress others or achieve a specific goal. They're not being themselves.
* Pretentious: The person is trying to appear more sophisticated, intelligent, or important than they actually are. They're putting on airs.
* Superficial: The person's actions are shallow and lack depth. They're focused on appearances rather than substance.
* Unnatural or forced: The person's behavior is exaggerated or strained, making it obvious that they are not being spontaneous or genuine.
Examples:
* "She was acting in quotation marks, pretending to be interested in his boring stories."
* "The politician was acting in quotation marks, making promises he knew he couldn't keep."
* "He's always acting in quotation marks, trying to impress everyone with his knowledge."
The quotation marks are a way of highlighting the artificiality and lack of genuineness in the person's actions. It's a subtle but effective way of conveying a critical or sarcastic tone.