Sometimes authors use short or abrupt sentences to get the reader’s attention. Short sentences and fragments tend to stand out. They can be used intentionally to jar the reader. Dickens was fond of long, rambling sentences. So you’d notice a short one even more!
I should mention that the conversation between Pip and the convict (Magwitch) in chapter 1 is made up of short sentences. These sentences being so short give the conversation a sense of urgency. Of course it’s urgent, because they could be caught at any minute!
“Tell us your name!” said the man. “Quick!”
“Once more,” said the man, staring at me. “Give it mouth!”
“Pip. Pip, sir.”
“Show us where you live,” said the man. “Pint out the place!” (ch 1, enotes etext p. 4).
Most of the dialogue is only two to four words long. Pip is terrified, and Magwitch is afraid of getting found. He’s in a hurry.
The awkwardness of this conversation is mirrored later in Pip’s discussion of Estella with Miss Havisham in chapter 8.
“I don't like to say,” I stammered.
“Tell me in my ear,” said Miss Havisham, bending down.
“I think she is very proud,” I replied, in a whisper.
“I think she is very pretty.”
“I think she is very insulting.” (She was looking at me then with a look of supreme aversion.)
“I think I should like to go home.” (p. 43).
In each case, the brevity of the dialogue and the prodding demonstrates Pip’s immaturity and fear.
Consider also the scene in chapter 4 at dinner. This sentence is short and stands out among the long-winded paragraphs.
Joe gave me some more gravy. (ch 4, p. 20)
This sentence also stands out because it is repeated, to the point where Pip is afraid to take more gravy. The repetition of gravy is comical, but it also demonstrates Joe’s preoccupation and discomfort with the conversation and the dinner company. From that same dinner comes the time when Pip’s sister mentions the pork pie.
Must they! Let them not hope to taste it! (ch 4, p. 22)
Pip worries that if she tries to find it, she’ll realize he took it. Then, he would either get in trouble for stealing it and eating it himself if he lies, or in more trouble for aiding the convict if he tells the truth. Luckily, the soldeirs show up.