Omitting articles in nouns - prepositions; after; to; before; from

Question

Why is the indefinite article omitted here?

Could it be the definite article, but omitted? Like in the following case in an instruction:

Grasp drumstick. Place knife between thigh and body; cut through skin to joint. Separate thigh and drumstick at joint.

All those omittions would normally have the definite article, but this doesn't seem plausible in my case.

Why is there no article here, too?

I've noticed that this happens only with the following prepositons:

before; after; from; to || day after day; from person to person; from teacher to student

My questions are: Why are the articles omitted in all those examples? Does it have something to do with comparisons? Is there any rule for this usage?

Answer 1

You have presented two different kinds of instances.

In the first and third examples, the omission of the articles represents standard usage. In both cases, the nouns represent abstractions: "teacher and learner" are not specific people, but instead represent roles in a hypothetical or generalized situation. "Question after question" represents no specific questions, but rather a generic and, one would think lengthy, series of interrogatories.

The second example is the sort of thing commonly found in printed instructions. The style is reminiscent of telegraphic, news headline applications. It may have risen from the need to economize on printed space, or the need to render the text simply for quick reference in a difficult and distracted environment.

(Fire alarm - break glass and pull handle)

It is also possible that it imitates a documentation style that originated among persons with limited English proficiency engaged in the international export of widgets.

Answer 2

All indefinite noun phrases begin with an indefinite determiner: a[n], one, two, some, many, ... All other noun phrases are definite. The definite article 'the' is required to distinguish mass nouns ('the water is good' vs 'water is good'), groups ('the two cats ate' vs 'two cats ate'), and it helps to separate individuals from concepts ('the cat is bad' vs '"cat" is a word'). In cases where definiteness is clear (from lack of a determiner on a count noun), 'the' can be omitted. It shouldn't be done too often, but it is common when space is limited. Note that proper nouns are typically definite in use, so we omit 'the' before names.