The Major made no attempt to keep dry-eyed
Having a man break down in front of another without shame during that time, even now, is largely unusual because of the masculine stereotypes put on men. This explains how awful the two must have felt being the first to see The Boy's body.
I am afraid to say how much whiskey we drank before the letter was finished. It had not the least effect on us.
Having the characters not even know how much alcohol they had to drink in order to cover up The Boy's suicide helps portray how wracked with guilt they must be, and can help create imagery and empathy from the reader as to how they must feel.
If he had been kept away from boots, and soap, and big dogs till he came to the trinity full-grown and with developed teeth, just consider how fearfully sick and thrashed he would be!
The author compared the boy to a puppy dog to try to explain to the reader about The Boy's character, to show us how innocent and naive of the world he must be
He said that he was "going to shoot big game",
In saying that he was leaving to shoot "big game" can be understood in several different ways by the reader. It could just be perhaps large animals, but it can also be foreshadowing to him in the end shooting himself, which would mean that he described himself as the big game. The author probably put that exact choice of word to get the reader thinking as to who that big game could be.