1,416. Whole Hallel vs. "Half-Hallel"

Hilchos Megillah v’Chanukah 3:8

The omissions made for half-Hallel are as follows: One recites from the beginning of Hallel until “chalamish lemaino mayim,” that God turns flint into a spring of water (Psalms 114). He then skips to “Hashem z’charanu y’vareich,” that Hashem, Who remembers us, will bless through Hallelujah (Psalms 115). He then skips again and continues with “mah ashiv lashem,” What can I give back to God, through Hallelujah (Psalms 116). Finally, one skips to “min hameitzar karasi Kah,” from desperation I called to God (Psalms 118), continuing from there until the end. This is the common practice but there are others. [Our common practice is to make the first two of those skips but not the third.]

Hilchos Megillah v’Chanukah 3:9

Hallel may be recited at any point in the day. One who recites Hallel out of order does not fulfill his obligation. If one reads with repeated pauses, he fulfills his obligation even if he paused long enough that he could have recited the entire Hallel in that time. On days when Hallel is recited in its entirety, one may interrupt in between the chapters but not within a chapter. On days when half-Hallel is recited, one may even interrupt within a chapter.