[asad hussain]

Could someone please have a look at the answers for 'grammar' and 'interpretation' mistakes?
After spending hours, days, even weeks on them I feel they are not quite right, and don’t sparkle. I am not sure if grammar, sentence structure, flow, punctuation, mood and tense are presented in a manner that makes sense. Could someone please do the checking, and make sure that the flow of readability of the answers is correct, and the style is consistent?
Here's the poem. The questions and their answers follow.

Stopping By Woods On A Snowy Evening

Whose woods these are I think I know.
His house is in the village though;
He will not see me stopping here
To watch his woods fill up with snow.

My little horse must think it queer
To stop without a farmhouse near
Between the woods and frozen lake
The darkest evening of the year.

He gives his harness bells a shake
To ask if there is some mistake.
The only other sound's the sweep
Of easy wind and downy flake.

The woods are lovely, dark and deep.
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep.

Stanza # 04 (All the questions below are related to Stanza No. 4)
Why can’t the poet wait to enjoy the beauty of the woods?
He can’t wait to enjoy the beauty of the woods because he too many responsibilities to fulfill, and has a long distance to travel before he can rest for the night.

Why does he repeat the third line?
He repeats the third line to make a strong claim to be the most celebrated instance of repetition in English poetry. The first "And miles to go before I sleep" stays within the boundaries of literalness set forth by the rest of the poem. We may suspect, as we have up to this point, that the poem implies more than it says outright, but we can't insist on it; the poem has gone by so fast, and seemed so straightforward. Then comes the second "And miles to go before I sleep," like a soft yet penetrating gong; it can be neither ignored nor forgotten. The sound it makes is "Ahhh." And we must read the verses again and again and offer trenchant remarks and explain the "Ahhh" in words far inferior to the poem. For the last "miles to go" now seems like life; the last "sleep" now seems like death.

Which letters have been repeated in the last stanza?
The letters o and e have been repeated in the last stanza.

Why have they been repeated?
They have been repeated to produce a profound impression.