It is years since I enjoy myself so much这句什么意思啊

it's years since i it is years since i saw him（追加）it is years since i saw him为什么不说it is years since i has seen him而it was years since i had seen him 却可以 it is two years since I came here还是it has been two years since I came here It is five years since he smoked It three years since I smoked.翻译 It is 5 years since I have lived here.It is 5 years since I lived here.这两句话分别译为? 翻译It is 5 years since that ...I keep it in my It is 5 years since that ... I keep it in my mind It ___ten years since i taught in the schoolA is B was C has D is it is four years since I joined the army.这里的is,为什么不用was呢? 请问It is six years since I last met you 与 It has been six years since I last met you 有什么区别 It ___ six years since I left school.空格填什么?It ___ six years since I left school.能填is,那has been 能不能填啊? It is five years since I came to this school.改为同义句I ---- ----- -----this school-----five years it is three years since i have seen himit is three years since i saw him有什么不同.表达效果还是意思什么的? 英语翻译it is 2 years since I bought the book.要求since翻译出来呀.Thank you It is ten years since I ___________ (leave) my hometown怎么填啊 英语翻译it is 10 years since I studied English1 帮我直译你们全错 哈哈 It is ten years since I got home last night..啥意思