He has five years more experience than I do./〔会社で〕He has been with the company five years longer than I have./〔学校で〕He was five years ahead of me in school.
彼女は同窓会の大先輩である
She is one of the oldest members of the alumnae association.
職場の先輩として佐藤氏を常に尊敬してきた
I have always respected Mr. Sato as a man of experience in this field [business].(▼seniorは通常年長を意味する.日本語の「先輩」のもつ特殊な意味は説明的な訳が必要)