Quote- "It was the worst thing I could've done, because the minute I started to laugh I thought I was going to vomit."

Response- In this part of the story, Holden was walking past two guys that were unloading a christmas tree and they were having a hard time. He just laughed but didn't feel so well. He had been having random headaches or stomachaches before that as well. I think that these radom surges of nausea was used in the story to help show that Holden feels lost and depressed about his future.

Quote: I thought I'd get pneumonia and die.

Response: This is after Holden met with Carl Luce and got drunk, after leaving he goes out into the cold night and thinks these thoughts. This shows that he is trying to think casual, as if he doesn't care about dying or getting pneumonia, it could be a facade of casualness that he wears and tries to integrate in his thinking to stave off overwhelming hopelessness, depression and fear for his future.

In "The Catcher in the Rye," Holden wonders on several occasions where the Central Park ducks go during the winter, when the lagoon they usually live in is frozen over. The first time he thinks of this, he is being lectured by Mr. Spencer after failing in his class, and the two other times he is trying to strike up a conversation with taxi drivers. When Holden is with Mr. Spencer, we are shown that he is rather absent-minded (he is thinking about ducks while his teacher is talking to him). When he is in the taxis, he is obviously very lonely, and tries to keep himself occupied with something very trivial to help him forget about his solitude. 
For most of the book, Holden is like a grumpy old man, complaining about this and that and angry at the world for a number of reasons. But when he thinks about the ducks in the Central Park Lagoon, he is showing us what's left of his infantile side. He is genuinely curious about what happens to the ducks, something seemingly irrelevant and unimportant. The ducks represent what little youthful curiosity there is left in Holden.

Quote: Chapter 1, Page 1
"If you really want to hear about it, the first first thing you'll probably want to know is where I was born, and what my lousy childhood was like, and how my parents were occupied and all before they had me, and all that David Copperfield type crap, but I don't feel like going into it, if you want to know the truth."

Response:
These are the book's opening lines. They reveal a lot about what is to come. First of all, you learn that the book is written in the first person, and it seems like it is going to be some sort of an autobiography (we know this because he tells us exactly the opposite). You also see that the narrator has a strong voice; he says "David Copperfield" type crap in the first sentence. He states his opinion, and tells us what he will and will not do. The writing style makes it seems realistic. It really sounds like a sixteen year old kid talking.

Quote: Chapter 13, Page 89
"Nobody's calling anybody a thief. All I know is my gloves were in your goddam galoshes." 

Response:
In this part of the story, Holden Caulfield is walking from Ernie's (a club in downtown New York) to the hotel room he rented. During his walk, he put on his red hunting hat and started thinking about his pair of gloves that was stolen from him when he was at Pencey. He thought of them because it was cold and he really wanted the gloves back. He was making up a scenario in which he found the culprit but would have taken the gloves back without a fight.

Holden's obsession with where the ducks from the Central Park Lagoon might be a way to distract himself from the loneliness of his life. He doesn't really have any real friends and his constant obsession with the Central Park Lagoon ducks, a question that he can never answer takes up the space in his mind when his usual negative thoughts lie idle. It may be something he returns to when his thoughts run out and he is left with the truth of things.