what does jack have trouble remembering

Is this question from your class? I don't recall this.

Oh, I see. It is a sentence in the chapter, Jack had trouble remembering what rescue was. Sorry about that.

Jack keeps forgetting that the boys have agreed that making shelters was EVERYONE'S top priority. Jack is intent on hunting, and Ralph is frustrated that he can't get any help.

"You remember the meeting? How everyone was going to work hard until the shelters were finished?” (Chapter 3)

Aslan's answer also fits.....

"Jack had to think for a moment before he could remember what rescue was.“Rescue? Yes, of course! All the same, I’d like to catch a pig first—”

Here is the sentence should you need it,

"Jack had to think for a moment before he could remember what rescue was."

Ch.3

The importance of jack's hesitation of what rescue means is that it shows the boys are mentally far away from civilization. The boys have stayed on the island for about one month already and has gotten used to its surroundings. They experience a different kind of living, different from the ones they have lived before. It shows how much they developed on this island