The definite article the is implied to point to something specific rather than indeterminate. It is clear that the nouns that have explanations after them should be preceded by the, like in
Walking around Prague I saw the house that was painted red.
However, if a noun is preceded by an adjective, which, by default, specifies the noun, should the be used, like in
Walking around Prague I saw the red house.
?
Or should a be used in both cases, because (painted) red is not specific enough for the definite article to be used? Would it be different for
Walking around Prague I saw the house where Queen Elisabeth lived.
Walking around Prague I saw the Queen Elisabeth's house.
?
What are the criteria that determine how specific is a noun, noun phrase or noun-adjective combination? I'm especially interested in the guidlines for scientific/academic writing.
Any help would be appreciated.
Best Answer
The means "one X we've talked about or seen before."
It means exactly one specific known/seen X - if there is more than one X, you can't use the unless you qualify the noun with adjectives so we know which one. The X can refer to a plural noun that is an indivisible group logically functioning as one "unit", i.e. the dozen eggs.
It also can be used with nouns that fall into a logical category of "one X that everyone should have seen or heard of before" or "only one possible X in the world."
Introducing a singular noun into a conversation with the indicates the speaker expects the listener to know which one on his/her own.
It's difficult to give general rules on when to use the versus a because the points above heavily depend on variable conditions outside of the conversation.
Is there a well-known red painted house previously known or seen both the speaker and listener? We then use the to indicate we are referring to it. If a was used, it means a red house was seen, but it wasn't anything special, and it wasn't a specific one known or seen before by the speaker/listener.
English, as you know, is full of exceptions. One of those is generally you do not use the in front of proper nouns that are the names of people.
Technically, you can do this, but you will be making the person sound "legendary" - as though he/she has done something so grand or unique that "one X that everyone should have seen or heard of before" or "only one possible X in the world" applies. So, in that case the Queen Elisabeth could work.