Complex sentence: Kanai was one of the last group of students of the founder of aikido, Morihei Ueshiba, entering the Hombu Dojo in 1958 as an uchi-deshi.
Split into simpler sentences: Kanai was one of the last group of students of the founder of aikido, Morihei Ueshiba. He entered the Hombu Dojo in 1958 as an uchi-deshi.