Split infinitives occur when additional words are included between to and the verb in an infinitive. Many readers find a single adverb splitting the infinitive to be acceptable, but this practice should be avoided in formal writing.
When he was 11 years old, Itachi was also under orders from his father to enroll in the Anbu half a year later. Itachi was praised highly by Fugaku, who spent most of his time grooming Itachi to inherit the title of leader of the Uchiha, and hence inadvertently neglected his younger son.
As the leader of the Uchiha clan, Madara's overuse of Mangekyo Sharingan blinds him, forcing him to take the eyes of his late younger brother Izuna. This allows Madara to use his newly awakened Eternal Mangekyo Sharingan to continue the ongoing war between the Uchiha and the Senju.