The two people in the middle were my homeroom teachers that year.
この場合、次のように言えますよ。
ーThe person on the far left is A.
「一番左の人はAさんです」
ーThe person second from the far right is B.
「右から2番目の人はBさんです」
ーThe two people in the middle were my homeroom teachers that year.
「真ん中の2人は、その年の私の担任の先生たちです」
ご参考まで!