I am still confused with some examples where the articles are not used. It's generally known that the articles A or An are used with singular count nouns however there are some examples where they are just absent. How could you explain that?
"In some sentences the true subject doesn't appear in  normal subject position."
The word position is a count singular noun however it isn't preceded by any of the articles.
"There can act as a pseudo-subject and is treated like a subject when changing  word order to a question"
here the word "order" is also count singular but it isn't preceded by any of the articles either.
How would you explain this phenomenon?