junior是指初级，senior指的是高级
例句
1.
My brother is my senior by two years.
我哥哥比我大两岁。
2.
She'll be racing for the senior team next year.
明年她将参加高级组别的比赛。
3.
It was an important meeting and a bad time to have a senior moment.
那是个重要会议，可不能犯糊涂。
