| Quote #1
[I]f I'd behaved sensibly, nothing more would have happened, everything else would have been nipped in the bud. (2.5)
K. believes that if he'd stuck to common sense (i.e., just ignored the court and all its weirdness), life would have quickly reverted back to normal. Instead, the court makes him self-conscious to the point where he questions everything that he does.
| Quote #2
In [the written defense], he would offer a brief overview of his life, and for each event of any particular importance, explain why he had acted as he did, whether in his present judgment this course of action deserved approval or censure, and what reasons he could advance for the one or the other. (7.2)
Since K. doesn't know what he's on trial for, he's forced to defend everything he's ever done. This defense is actually an autobiography, where K. must interpret and justify his actions to the court. Writing the defense is also a process whereby K. can attempt to figure out what exactly he's on trial for.
| Quote #3
In the end K., who was now simply glancing mechanically back and forth during the conversation, began to fall prey to his earlier fatigue and at one point to his horror caught himself, just in time fortunately, starting to rise absentmindedly, turn around, and leave. (9.2)
As K. gets better at interpreting the world of the court, he gets worse at interpreting everyday conversations, as he loses track of this particular conversation.