Why can you do dinner for breakfast but not dinner?

This is a bit of a wordplay trick! Here's why:

* Dinner as a noun refers to the evening meal.

* Dinner as a verb means to have dinner.

So, "can you do dinner for breakfast" is asking if you can *have* dinner for breakfast, which is perfectly acceptable.

However, "can you do dinner" sounds like you're asking if you can *perform* the act of dinner, which doesn't make sense.

It's a play on the double meaning of the word "dinner"!