I'm a university student of English and we are studying "Articles" in our grammar module. Our teacher gave us this sentence, "You have egg on your tie." And asked us why we haven't used an article. Could someone tell me why?
1. You have egg on your tie.
Without an article, egg is being used as a mass noun. It's quantifiable, but not countable.
It's effectively the same as saying:
You have some amount of egg on your tie.
It could be a teaspoon worth of egg material or a cup worth. (Or any other measure.)
2. You have (an / the) egg on your tie.
This means that you have a single egg on your tie.
Most likely, although strange, it would also imply that the egg is whole (otherwise I suspect it would be something like you have the content of an egg on your tie)—although that certainly doesn't have to be the case.