one year ago 是具体时间吗可以用 have been 吗

one year ago 是具体时间吗可以用 have been 吗 One Year Ago 歌词 since one year ago 可与延续性动词连用吗应该是现在完成式 有one year ago这样的说法吗? one year earlier 是不是以现在为基点,往前推?写文章的时候,想写“在1年前发生的事”听说one year ago,是以现在时间为基点,往前推.是用“one year earlier”还是“one year ago”好呢? 为什么是one year ago而不是ago one year?one year ago的话词性上来讲说不通啊 last year=one year ago 去年.一年前? one year ago 和a year ago 没有任何区别吗?可否说明一下：one 和a 在任何情况下都可以互换的吗? he has kept a car since one year ago（对since one year ago 提问） 歌曲one year ago 的歌词中文意思 He drive much____than he did one year ago.(careful/carefully) She ____(move) to Paris one year ago. one year ago和one year earlier区别?写文章的时候用哪个呢? one year ago和one year earlier区别?写文章的时候用那个好呢? i was a student one year ago.(变成一般疑问句）（ ）（ ）a student one year ago? 问Who is Ampere?答 It was more than one hundred years ago a great French scientist这句语法有错误吗more than one hundred ago 是时间状语还是定语呀?who was ampere? have (现在完成式)后面加时间段,那么since one years ago是点时间还是段时间?意思不是在一年之前吗? for one year=since one year ago=如上,还等于什么（）is a year()