The word vale, adds a scholarly feel to the poem, and allows the poem to flow better overall. It is also a huge difference in the rhythm, as it has only one syllable rather than two.
The word margin was used to add a new taste of vocabulary. Margin's other meaning is "an amount by which a thing is won or falls short" so in using this word, one has the feeling that it is almost but not quite the analogy used. So it's an implication to the poem's analogy itself, giving a sort of fourth wall experience.
D. Emphasize because of the use of how she said it "loudly and clearly" meaning she wanted it to be known, or emphasized
Where they differ from one another is that a colony is ultimately administrated from the mother country it belongs to, and thus has no say in its governance, whereas in a state they have strong political representation within a nation. ... The United States in the past also maintained several Colonies around the world.
the house of representatives and the senate
