994. Reading the Megillah from a Book

141:15 If a person has a non-kosher Megillah or the text of the Megillah in a printed book, he should not read aloud along with the reader because he will not be able to concentrate on hearing the words. Even if he is able to concentrate, there may be another person who hears what he is reading and that person will not be able to concentrate on hearing the reader. Similarly, one may not assist the reader by reciting the Megillah from memory. Therefore, when it comes to the four verses of redemption that the congregation recite aloud, the reader must go back and read them from his kosher Megillah (lechatchila - that is to say, he should do so. After the fact, he need not go back - Mishnah Brurah 690:16).

141:16 Let's say that a certain person has already fulfilled his obligation of reading the Megillah and he is now reading it a second for another person. If the one for whom he is reading knows how to recite the brachos, he should do so. (The commonly-accepted practice is for the one reading the Megillah to recite the brachos in any case - MB 692:10.) If he is reading for a woman, it is preferable for the reader to recite the brachos and to conclude, "Who sanctified us with His commandments and commanded us to hear the Megillah," rather than "on reading the Megillah."