R' Yehudah says: We must search on the evening of the fourteenth, or on the morning of the fourteenth, or at the time of removal.  But the Sages say: If one did not search on the evening of the fourteenth, he must search on the [day of the] fourteenth; if he did not search on the [day of the] fourteenth, he must search during the festival; if he did not search during the festival, he must search after the festival.  That which he leaves over, he should place in hiding, so that it not be necessary to search for it [again].

R' Meir says: We may eat [chametz] the entire fifth [hour], and we must burn [it] at the onset of the sixth [hour].  But R' Yehudah says: We may eat [chametz] the entire fourth [hour], but we suspend [it] the entire fifth [hour], and we must burn it at the onset of the sixth [hour].