it's been six years since we last saw each other是个什么从句?

it's been six years这句话什么时态 been 的作用与时态 he's been in Japan for six years.=it ___ six years ___ he came to Japan ‘It's been six years since we last saw each other’怎么翻译? it's been six years since we last saw each other是个什么从句? He’s been learning English for six years and really loves it. Kate has been to Mexico for six years.It's years__Kate__to Mexico.改为同意句怎么填 He's been learning English for six years and really loves it.中为何用loves?不用loved? wei ming feels differntly.he's been learning english for six years and really loves it.he thinks st he's been 是什么的缩写在He's been learning English for six years and really loves it.是is还是has其他地方怎么区分 it's seems like years since it's been It’s six years since we knew each other同义句 we （） （） each other for six years. It has been six years since I began to study English. 怎么翻译? 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? He's been learning English for six years.改为同义句 It's+been+in+Boston+for+over+250+years. it's been ten years 为什么不加for It's six years since we knew each other(改为同义句）