There are several types of phrasal verb, and several types of verb + preposition. Not all of them are constituents, they serve different functions, they're all irregular as hell, and they're all governed by the matrix verb.
Every verb has its own assortment of special idioms, affordances, prohibitions, requirements, and irregularities. There is such immense variation in these details that such matters are considered part of the meaning of the verb; certainly they are strongly affected by the meanings. Square and cube that variation for phrasal verbs, since there are far more phrasal verbs in English than there are single-word verbs.
Some varieties can be examined in this freshman grammar homework problem. Examples of different types, from there:
Sentences (1) and (2) show two normal verb + prep constructions, from the same verb: look at, with transitivizing at; and look for, a transitive idiom meaning 'search'. Both of them require that the preposition precede the object (which may be thought of either as the object of the preposition, or as the direct object of the transitive verb + prep construction), even if that object is a pronoun. It makes no difference to most prepositions whether their object is a noun or a pronoun (ungrammatical sentences are marked with an asterisk *):
- I looked for Einstein ~ *I looked Einstein for ~ I looked for him ~ *I looked him for.
Sentence (3), on the other hand, is a real transitive phrasal verb. There are two characteristics of phrasal verbs that help to distinguish them. Both tests have limitations, however. The most important one, and the easiest test to administer, is the difference between the pattern of asterisks in the second and third columns, where pronoun objects force the difference.
There is a syntactic rule (called Particle Shift in the literature) that applies to transitive phrasal verbs only, and imposes a special requirement on pronoun objects. Thus, with a real phrasal verb like look up 'research (v)', the particle may appear either before or after a Noun object, but must appear after a Pronoun object.
- I looked up Einstein ~ I looked Einstein up ~ *I looked up him ~ I looked him up.
Note, however, that this test is helpful only with transitive phrasal verbs. There are plenty of intransitive phrasal verbs, too, but there's no object to test with. Many transitive phrasal verbs can appear also intransitively, e.g take off, move away, often with a different sense (He took it off ~ The plane took off), or not (He moved it away ~ It moved away).
The second useful characteristic is that a phrasal verb is stressed on the particle, at least as much as on the verb, and maybe more. A V + PP construction like look at, on the other hand, is stressed on the verb, not the preposition.
- He looked up the word. ~ He looked at the word.
That's because prepositions are rarely stressed, except for emphasis (In the toilet, you idiot!);
they're sposta slide by like articles and conjunctions to grease the way into the object, which is the informational part. They're not sposta distract, so they're unstressed, and therefore reduced, so we get common contractions like sposta and lookit.
Unfortunately, stress is not represented in English writing, so that distinction is not helpful for readers.
Things which can be in a mountain are principally those which intrude inwardly upon its profile or its expected profile, or are entirely encompassed by its expected profile. For example, there can be a hole, or a ravine, or door in a mountain, -- as there can be a hole in an apple, -- because they are inward projections or modifications when compared to the expected profile of the mountain. "The door in the mountain leads to a magical kingdom".
There can be gold, or other minerals, in a mountain, -- as there can be a worm in an apple, -- as they are encompassed by its profile. But these are also inside the mountain (or apple), which includes only those things which are in a mountain and which are also not evident from its surface. In these contexts inside is more likely to be used, but in is also correct. "There is a dragon inside the mountain".
More generally, surface features of any kind are on the mountain (including those things which are in the mountain but not inside it, such as ravines). This includes boulders, ravines, and tea shops. "There is a tea shop on Mount Snowdon".
Something as fundamental to a mountain as a peak, however is of the mountain, as it is a fundamental constituent part. In contexts where, for example, a dragon is known -- distinctively and crucially -- to sleep inside Mount Fire, it can be referred to as the dragon of Mount Fire as it is an important constituent of that mountain. "The north face of the Eiger is hellish".
Prepositions are slippery and complex in all language. Good luck.
Best Answer
"at" every step vs. "on" every step.
In both phrases, both "step" are nouns; but, different nouns.
If "at" is used, the "step" is what a person makes while walking, one step at a time. Therefore, "at every step" a reader is going to imagine a person is actively walking. Also, that something else is occurring in the background during every step that person takes. (Example: "The monster was behind her at every step." [No matter which direction the girl walked, the monster was right there behind her] - It can also be a "step" or procedure like below with "on," so it's important to read what's around this phrase to ensure you're taking it in the right context.
If "on" is used, the "step" is a different noun as another poster pointed out. "On' turns the emphasis away from the person taking action, to emphasis the step as more crucial. "Step" - It could be a physical step on a staircase, or ladder, or, like cited last above, a "step" or a specific procedure one must do or follow in constructing or assembling something.
(Example #1: While climbing the ladder to pick cherries, "Warning: Serious Injury May Occur if extended beyond 5 Meters" was written on every step.) ..that is, each and every ladder step had this warning on it to ensure a person wouldn't extend the ladder beyond what it was safely designed for.
Example #2: "In building any model airplane with high voltage, safety equipment must be worn on every step, when performing steps 8 thru 14 below:" [Whenever steps 8 thru 14 are performed, no matter which step it is between 8 and 14, safety equipment is necessary to prevent serious injury.)
To answer your question, you seem to be translating some kind of 'life lessons" work where steps are metaphoric, like in steps you take in life or decisions you made at specific turning points ("turning points" - metaphor for path or step.) Therefore, apply what I wrote in paragraph 1 (at) if emphasis is on the actions of the person, which this fits best, since at every turning point where action was required, the narrator chose to deliberately protest & object. Apply paragraph 2 (on) if you decide emphasis is better stressed when placed on the step or path (every path - metaphor for any and all good or bad paths a person could take in life) the person has been on all these paths, and no matter which kind it was, just protested 7 objected.
If this is the case, which I think it is, that your translating a metaphor for life's steps taken along the way, either one works; but, the stronger impact is "at" - since life is active and "happens" based on what we as living people do or don't do in our lives that have real impact or effect, so I would choose "at." Why?
The "stressor" in the poem is on the person and their decisions at life's critical points, so use "at." If you as the writer or translator, however, is attempting to stress the "path" like the right path..being on the right path is sure and secure, and a person didn't follow it, or on the "right steps" in a marriage were taken = happy; weren't taken = full of troubles, "on" puts the writer's stressor on the path or the step, so then use "on."
In metaphor, it's up to you as the writer to point me as the reader concisely what you're trying to convey. I Hope this helps.
To apply above to your work:
"At every step, at every path, I've protested/objected"
Me (Reader): I read this and think the 1st person (writer), all along the way in life ("step" "path" = metaphor for "life), this person has constantly protested and complained. (Summation: This person has come to a crossroads in their life where they see they've lived wrong in the past and it's a pinnacle point to awareness as first step to change behavior for the good) Emphasis again is on the actions (metaphor for path or step) the narrator has taken.
"On every step, on every path, I've protested/objected" Me (reader): I read this and think no matter if this person was on a good path or bad one ("every step" "every path" - metaphor for living good life or living a life of crime - as "both" encompass "every path" even down the sexual ones or study ones..no matter the path, it didn't matter. This person complained, protested, and objected whenever doing right or wrong, or anything-everything, nothing mattered and "I've protested/objected" - is a firm statement this person is not going to change no matter what new "path" or step you might propose to them to follow, they're not going to do that, either. Emphasis is on a good life or bad life (encompasses "every" path) and this person still complains either way.