a person who gives a younger or less experienced person help and advice over a period of time, especially at work or school 导师
tutor: /ˈtjuːtə/
Link to original
(especially BrE) a teacher whose job is to pay special attention to the studies or health, etc. of a student or a group of students 导师；指导教师
his history tutor
他的历史导师
He was my personal tutor at university.
他是我大学时的个人指导教师。
She’s in my tutor group at school.
她在学校里是指导我的那个小组的成员。