[If] one recites the Shema and does not make [it] audible to his ears, he has discharged [his obligation]. R’ Yose says: He has not discharged [his obligation]. [If] he recited [the Shema] but was not meticulous in [enunciating] its letters, R’ Yose says: He has discharged [his obligation]. R’ Yehudah says: He has not discharged [his obligation]. [If] one recites [the Shema] out of sequence, he has not discharged [his obligation]. [If] one recited [the Shema] and erred, he must return to the place where he erred.