Learn English – Use of seemingly wrong grammar in the poem(s)

1. Your understanding of the sentence is correct—it means that Harry's room is the one on the right.

2. It is grammatically acceptable, but a sentence that is grammatically correct is not necessarily meaningful. In this case, however, it is understandable, but your phrasing of the sentence would be the complete form.

3. Personally, I would not use this construction; it's a rather unusual one. Using this sentence might imply familiarity or distraction, depending on the observer.

4. I can think of several, but they are not in the same style as your quote. Most sentence of this type, such as You are my doll, use meanings that have become embedded in the language and are reported on in dictionaries. Sentences like those in your quote are extremely unlikely to be encountered and I would not recommend using them.

In leaves no step had trodden black.

This line refers to leaves that have been stepped on to the point where they are black instead of the color they were when they fell off the tree.

The word "tread" means (one of its meanings) "to step on." So you can tread on the leaves as you walk along. If you have stepped on the leaf, we can say you have trodden on it.

So the speaker is saying (at this point) that that road has not been walked on. The leaves have not been stepped on so they have not turned black from being crushed or ground into the dirt or anything.

And that has made all the difference.

In this case, the narrator, reflects that, of the two paths he could have taken in life, he chose to follow "the one less traveled by," and he believes "that has made all the difference." Basically, the narrator reached a point in his life when he was faced with decision to either conform to society and live a "normal" life, or to live his life in way that embraces individuality or an less conventional existence than the first path.

The road that fewer people had taken ("was more grassy and wanted wear") was more inviting to the narrator, so he made the choice to follow the path that fewer people had taken. The narrator believes that chosing to follow the norm would have been the wrong decision.

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