Do you mean any rules at all? Or a particular set of rules? :-D
If you’ll pardon a shameless Star Trek (2NG) reference, my mirthful responses speak to the vagaries and sometimes needless nuances of the English language. In the episode “Darmok” our fearless friends encounter a race of beings whose language consists of cryptic metaphors: “Temba, his arms wide”. Our intrepid crew must find a way to communicate or face dire circumstances (as was usually the case in each episode). The clock is running!
The fate of the human race doesn’t rest upon my deciphering the gradations of meaning between “going to hospital” and “going to the hospital” and to any criticism on (of?) my deficiencies in English I blame the advent of mini skirts in junior high school (I didn’t get much done my entire sophomore year ;’}