Formal:
* The defendant's personal life was irrelevant to the charges against him.
* The study's results were irrelevant to the current situation.
* The argument was irrelevant to the main point of the discussion.
Informal:
* That's irrelevant to the conversation, can we please stay on topic?
* I'm sorry, your opinion is irrelevant to me in this case.
* Whether or not you like pizza is irrelevant, we're having it for dinner!
Humorous:
* The fact that my cat can open doors is irrelevant to the fact that I need to find a new lock.
* My dog's opinion on what I should wear is irrelevant, but he's very vocal about it.
* The color of my socks is irrelevant to the outcome of this football game, but I like to wear lucky socks.
Literary:
* The details of their childhood were irrelevant to their present predicament.
* The old man's wisdom seemed irrelevant to the young girl's dreams.
* The beauty of the sunset was irrelevant to the storm brewing on the horizon.
