Please help me to understand "It has been ten years since he lived in New York" really means Here are four sentences: 1.It has been ten years since he lived in New York 2.It has been ten years since he has lived in New York 3.It has been ten years since he was a teacher 4.It has been ten years since he has been a teacher What I know is sentence 1, he doesn't lived in New York now. sentence 2, he still live in New York today. sentence 3, he is not a teacher now. sentence 4, he is still a teacher today. The question is, if this man lived in New York from 2004 to 2007(3 years ), and then, moved to another country in 2007, should I say "It has been ten years since he lived in New York" or "It has been seven years since he lived in New York" same question, if this man became a teacher in 2004, and quit his job in 2007, should I say "It has been ten years since he was a teacher" or "It has been seven years since he was a teacher" Thank you for answering my question