16. [The following is the law] when a person who has already fulfilled his
obligation to hear the Megillah, reads the Megillah again for a colleague
who has not fulfilled his obligation: If the later is able to recite the
blessings preceding the Megillah on his own, he should do so. If, however,
one is reading for a woman, it is preferable that the reader [alter the
text of the blessing and] recites: "...asher kid'shonu b'mitzvosov
v'tzivonu lishmo'ah Megillah" (1) (ending the blessing with "...commanded
us...to hear the Megillah" rather than "to read the Megillah") (2).
(1) Some say "lishmo'ah MIKRAH Megillah" (Mishna Berura 689:8).
(2) This is because a woman might be obligated only to hear the Megillah,
but not to read it (Mishna Berurah 689:7). If a woman has nobody to read
for her, she should read it for herself from a kosher Megillah, but should
still end the blessing preceding the Megillah with ".,,Li'shmoah mikrah
Megillah" ("to hear the Megillah") (Ibid. 689:8).